Buddy Complex

Our main characters from both series were living a normal life until a fateful encounter changes their lives forever. Haruto Tokishima must pilot a mecha called Valvrave to save his friends. Aoba Watase must pilot a mecha to save a distant future. Both characters will meet their polar opposite counterparts—L-Elf from Valvrave and Dio from Buddy Complex. I will even add that Saki and Hina are very similar yet different. Both series share the same company (Sunrise) and character design. They even share the same personality to some extent. If you miss Valvrave and need another series to fill the void, I recommend Buddy Complex. 

Ledo from Gargantia and Aoba from Buddy Complex are sent to another time/universe. Not knowing what will happen to them, they must adapt to their surroundings and find allies to help them get back home. Solve this world's situation and uncover secrets hidden within them. This secret will change them forever. Ledo has been trained for military combat while Aoba has none of that yet. They must live a life they are not used too or else suffer the consequences of their actions. 

Both anime have some characters that will hate each other and then like afterward from fighting, and these two similarity are that they use mecha to fight and the story feel kinda identical if you like one you might like they other, but then when you watch both anime you can see the different as well but the concept still apply 

Aside that boyh have the same genre, the premise is very similar too: Main character goes into this new world (74 years in the future or out of the dome thingy), and their relationships with their new aquitances is very similar in both of them (Main female aside). 

Similarity : Both anime featuring a unique system which enables two or more users to share experiences, abilities, and skills; all while increasing the abilities and output of theirmake their mecha units as well. Siegfried system (Soukyuu no Fafner) : Operated by Minashiro Soushi This system taken to the extreme, not only do the pilots synchronize with their Fafner units, but they are also linked with Soushi mind via the Siegfried system, which allows him to guide them while forcing him to feel all the pain they feel. Coupling system (Buddy Complex) : This system allow two Valiancer pilot connected their mind which can make unlock special power such combine their aeroscales, back-to-back, and manifest a small force field that could dissipate oncoming attacks.  read more 

- Both series involves action, mecha/military and romance theme - Both series has a slight element of school setting - Both series takes place in the future, sci-fi genre - Male MC are professional robot-users - Both series male protagonist protects female protagonist - Both series uses mecha robots for military use Both series reminds of each other even if they have a decade release date in between them. Even though FMP is from 2002, the animation resembles Code Geass animation, and therefore you should not worry about the quality/art. 

The premise is similar, two pilots of giant mecha can combine (Vandread is a physical combo, whereas in Buddy Complex it is mentally). Both anime feature a male lead, and follow their journey with a group of friends and allies to stop an enemy. 

Both have robots and a futuristic setting. The protagonist is a friendly and courageous newbie that has an excellent knack for operating their robot. Both anime feature robot synchronization and are fighting their battles with a team against an opposing force. The teams are both led by eccentric captains that have a wise streak. 

*Both have large scale flying mech battles. *The characters are soldiers in a flying ship. *Theres an overarking mystery about the main character that gets resolved by the end. *Both have super OP Maincharacters 

both of these anime are surprisingly similar. let start with the themes : valvrave theme were - mecha , friendship , death and Yolo, vampires while Buddy complex themes are : mecha , friendship and death . these anime are similar because they are like any other typical mecha anime , a inexperience teenage piloting giant robots , basically the stuff they show you in Gundams  

Both are Sunrise Mecha series that deal with a romance that crosses faction lines, although said romance doesn't take center stage until about halfway through the series in both cases, and they also feature a lot of character drama and well animated combat.  

Both are time travel-centric shows where the main character is taken from his time to the far future, with a message from a girl telling him he'll be important to the plot (basically). Both also come with all the head scratching foolery that usually comes with a time travel plot, but have fun enough action that they're enjoyable even if the storylines and writing are questionable. 

Both series use their primary mecha's functions (the tandem piloting style in FranXX and coupling system in Buddy Complex) as metaphors/allegories for relationships and sex, and they deal with how the pilots' interactions and relationships change as they deal with these systems. Both series also heavily retread established tropes and plot elements of their respective studios (Trigger for FranXX and Sunrise for Buddy Complex). 

I can't say much about Buddy Complex yet as there are only a few episodes that have aired at the moment, but from what I can see of this anime, it gives me a similar atmosphere to Eureka 7. Both anime have mecha and (spoiler alert for Eureka 7) the idea of the future and past. Both amine are set in the future, and have a mysterious girl that comes into the main character's life. The ship in Buddy Complex really reminds of of the Gekkou in Eureka 7, though BC's is blue, while E7's is green. If you enjoy Buddy Complex, I highly recommend that you watch Eureka 7 and vice versa. read more 

They look like us are both mecha and fighting to save humanity 

TIME WARP PARADOX STORY That words tell everything about both anime Similarity : + MC came from different time using wormhole created from some incident testing, the difference is "Little-Girl" (Urda) came from future while Watase Aoba(Buddy Complex) come from past + MC rescued by his/her partner to join with protagonist side, fighting again antagonist side & also finding a way to return to his/her time, The partner is Little-Girl with Erna, Watase Aoba with Dio Weinberg Junyou + Main enemy also similar : Kurtz Glimhild (Urda) & Gerafil Bizon (Buddy Complex) originally a good person but turn become main enemy because time warping  

Both are mecha anime, that are full of action. And both give out the same feeling. Neither are too unique, but still well done. If you like one try out the other one, you'll definitely like it 

Both anime use machines to fight in battle. Hina Yumihara protects Aboa Watase in order for him to meet Jyunyou Dio Weinberg while Kira Yamato protects his friends and helps them to bring an end to war and bring peace between Naturals and Coordinator's. Gundam Seed Destiny doesn't just evolve around just one person but multiple as they fulfill their own role in the story. Buddy Complex revolves around two boys who are coming of-age as they both come together and change the fate of the world  

Buddy Complex and Gundam SEED involves a war between factions in a sci-fi environment. Both series' main male protagonist becomes a pilot of a gundam/mecha to fight for what they believe in. There is a complexity of supernatural elements involved in both series that makes a big difference in the war. Plenty of action is offered as mecha warfare takes the skies and power struggles become a central struggle between the allied nations. 

Both series are mecha , and both protagonist are living a normal life until their lives are changed forever. Kyouno Madoka's life as a Jersey Club member changed when an alien named Lan asks her to pilot a robot , Watase Aoba's life turned upside down when a girl from his class saved him from a Valiancer claiming that she is from the future. Coupling in Buddy Complex is somehow kind of similar in Rinne no Lagrange's memoria. Coupling can be done by two pilots that share the same brainwaves and an invisible bond is formed within them while the memoria in Rinne no Lagrange is a kind of bond the pilot and the robot share that the only people who have the memoria is the only one who can pilot the robot. The only difference between both series is that the protagonist from Rinne no Lagrange is a female while the protagonist from Buddy Complex is a male.  read more 

Similar system : Pilots simultaneously connected there mind and body into a single coordination to access new power & new mecha form Different : + Bradyon & Nexon are not required to perform "coupling" process because limited time (only activated for 15 minutes atleast). + Aquarion required coordination from 3 pilot since aquarion body is not single unit but consists of 3 different parts & 3 different pilots  

Similarity : Partner System This system is very important in both anime. In Simoun, To protected from another country attack, Simulacrum Kingdom is defended by advanced airships known as "Simoun" which must piloted by two woman priestesses known as sibyllae. The sibyllae can inscribe enormous glyphs known as Ri Mājon in the sky using the Simoun to produce powerful magical effects both for combat and ceremony. This "Ri Majon" only can be created by two sibyllae. In Buddy Complex, Buddy System is main weapon from Free Pact Alliance to counter invasion from Zogilia Republic. This system require two pilot to perform "Connection" which giving ability FTL-like speed move.  read more 

If you liked Buddy Complex can't go wrong with an older mecha series. Sometimes older series lose interest of a younger fan base because of animation style and the time period of the writing. Still worth a watch.  

Similarity : - Team works is the main key when fighting - Mecha unit have a time limit to operate (Dancouga Nova only have 5 minute & Luxon-Bradyon only have 10-15 minute) Different : - Different theme story - Different enemy 

Fuzzy physics (time travel vs parallel worlds), mecha, unique protagonist (only male that can pilot mecha vs universal coupler), underwhelming odds against superior empire, brainwashed female lead 

Ouma Shu = Tokishima Haruto Tsutsugami Gai = Dio Yuzuriha Inori = Yumihara Hina Both have main protagonist pulled out of everyday school life without experience in the battlefield Similar Mechas High Budget Shu+Inori.....Aoba+Dio Similar how 2 of them pairs and becomes extremely powerful Gai has similar personality to Dio Both anime have main protagonist protecting a girl