For reference, regarding the Hibari HP AU, it is very much an ‘everything is exactly the same except Hibari is there’ thing. Harry Potter actually has to suffer this bizarre Hufflepuff who has decided to camp out in Fluffy’s room as his yearmate.
(Other character facts: Dino is a fourth-year Hufflepuff who gets to be a prefect in fifth year, Tsuna is a weedy Gryffindor of the most noble and ancient house of Vongola, Gokudera is a Slytherin that is absurdly good at potions, Xanxus & Crew are seventh year Slytherins that run an information business out of Hogsmeade once they graduate, and Yamamoto & Ryohei transfer from Japan into Gryffindor in third year. Neither of them speak English. Both of them are muggleborn. Both of them chase Tsuna around because he speaks Japanese. Hibari speaks like 8 languages but Kusakabe has trained him to talk in Mandarin and nothing else every time someone tries to utilize his language skills.)