For the AU headcanon ask thing if you're still doing it (sorry for bugging you if you're not): Parental Soulmates with Aizawa and Izuku? Or just a soulmate au for your fave pairing if that doesn't sound interesting!
!!! I am absolutely still doing it!! Parental soulbonds my beloved tyyy (and you’re never bugging me! :D)
1. It’s a writing-on-skin bond, and they first realize it because Shouta is in a Rush and writes some Very Important notes on his arm and Izuku sees them and is... very confused, to say the least
2. they meet irl on accident! they bump into each other at a grocery store and Izuku starts rambling and Shouta is reminded of his soulmate, and he knows his soulmate is a small child and so is Izuku so he takes a chance and asks him if he’s The Kid
3. Inko is very pleased about all this because Hisashi left since he’s a bastard so shes glad Izuku has another good role model in his life
4. sometime after that, Izuku asks Shouta if quirkless people can be heroes, and Shouta says that he doesn’t know because, let’s be realistic here, but Izuku convinces Shouta to give him one (1) lesson in parkour/something-else-that-can-be-applied-to-hero-work to see how Izuku does and while he isn’t immediately the best ever, he’s good enough for Shouta to start semi-regular lessons
5. Shouta secretly takes Izuku to the recommended exam by telling him that the Regular exam was moved up a day. Izuku is super surprised but concentrates enough to pass the exam!! He gets into Class 1-A because Nedzu knows shouta will be a hard-ass no matter what (ie no slacking off because of Dad Rights)!