If you liked
Fullmetal Alchemist: Brotherhood
|
...then you might like
Hunter x Hunter (2011)
|
FMAB is slightly darker, but both anime share the same adventure style and comedy with a similar sort of style. They both involve a young, male protagonist, and their determination for their individual goals. Lots of interesting/ slightly odd characters and creatures that feature in both.
If you liked
One Piece
|
...then you might like
Hunter x Hunter (2011)
|
Similar adventure style with lots of action, and mainly features around the protagonist (Gon in HXH and Luffy and his crew in One Piece). Like how Gon's goal was to become a Hunter etc, Luffy's goal is to become the pirate king, so they both have that similar sort of drive as characters.
If you liked
Kuroshitsuji
|
...then you might like
Fullmetal Alchemist: Brotherhood
|
In terms of style, Kuroshitsuji is a lot darker than FMAB. Although both do share these incredibly dark moments. The main comparison is just that despite FMAB's darkness, it still includes comedy, whereas Kuroshitsuji is mainly just dark. Both have excellent music, and screenplay. Both allude to the struggle of the main character (Ciel in Kuroshitsuji, and Edward Elric in FMAB) and their hope of understanding/ correcting their past.
If you liked
Kaichou wa Maid-sama!
|
...then you might like
Ookami Shoujo to Kuro Ouji
|
Similar storyline and characters. Both involve the main narration of the female lead and her love interest with a boy from the same school. Both interesting stories, with slightly different approaches.
If you liked
Shigatsu wa Kimi no Uso
|
...then you might like
Kimi no Na wa.
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Deeply moving, beautiful music. Both highlight the inner struggle and the influence of other people in understanding this struggle.
If you liked
Koe no Katachi
|
...then you might like
Kimi no Na wa.
|
Not similar in the sense of storyline, but a sort of similar style. Both deeply moving. Both involve two main characters and their journeys of understanding themselves and those around them.