#but his true form as obevort outright uses the abyss element

[kotaerukoto]

-- Well-known in Mondstadt among the patrons of its bars, and probably has had a few run-ins with the Knights of Favonius because of how he doesn't pay his goddamn tabs or pay back money he's been lent. Still, he's not disliked, and in fact has quite the rapport with many of the people he has met!

-- Identity is influenced by the Shakespeare character Oberon and records of his myths brought over from a different world. How did they end up in Teyvat? Well, Alice brought them over, probably... Still, he's cursed, everything he says becomes a lie, and he yearns for the fictional Titania. Not too different from his canon here.

-- probably more I need to keep thinking and reading more genshin lore to figure out how I can fit him in

First thoughts for Genshin Obie:

-- King of Fairies from a small, secluded forest near the Mondstadt area. The fairies in question are extraordinarily weak ones and he's only a "king" because they decided to call him their king, and he too bills himself as someone without much fighting ability. Anemo Catalyst user, he fights using weapons made of dead insects. Vision is fake and he wears it for appearances. He's not an Allogene.

-- True identity is the Insect of the Abyss/Abyssal Worm, an entity who, if completely unleashed, can destroy Teyvat in a planetary and conceptual collapse. Not an understatement. Nobody knows this except Oberon, and his main goal is to unshackle it so that it can destroy everything.