as there was a meeting with the pro heroes, Aizawa had Eri with him but something happened and Eri used her quirk causing the pro heroes to be teenagers again

Aizawa: Oh no!? Eri what did you do!

Eri: s-a-sorry…

All Might: this might be bad.

Endeavor: Why!!

Hawks: Hehe! Nice!

Best Jeanist: this is interesting… Mirko: Oh boy I’m young again! Mt. Lady: Awesome! Midnight: Sure is! Ms. Jokes: We’re young! Aizawa marry me!!

you are also a pro hero but you are not a teen but a 6 year old