Gegege no Kitarou (2007)

Story about a one-eyed protagonist of supernatural origin and his interactions with human world. 

Episodical show about group of youkai friendly to humans that fight youkai that cause problems for humans. Both are remakes of much older franchises. 

Both feature Youkai (Japanese monsters, spirits and demons), though Gegege is closer towards the original definition of scary. They each have a different take on Youkai, with Gegege being more traditional, while Youkai Watch has a more modern approach and setting. Gegege no Kitarou is a long-running series in Japan. Both anime are relatively obscure outside Japan, so it might be difficult to find translations. While Gegege is more about the lives of Youkai being what they are, Youkai Watch is about a human boy interacting with Youkai. 

Both animes deal with the main character fighting against demons known as yokai's, and both have a lot of other strange characters. They are both very interesting to watch.