Honkai Impact 3rd has a few anime series that are not canon to the main story, although canon events are sometimes referenced in it. All of them are hosted on the official Youtube page.

Cooking with Valkyries[ | ]

Cooking with Valkyries is an anime series that features the Valkyries cooking recipes, which are also showed at the end of each episode. There is also a manga based on some episodes.

ELF Academy[ | ]

ELF Academy is an anime series in which the ELFs visit a special academy and hilarity ensues.

ELF Academy Playlist