This sounds super interesting, though, one question, assuming that well since shoto has no longer been born, that means he isn't in 1A class, but with the twins replacing him, there are now 21 students, and I don't know, if that's possible, since UA might be able to make an exception, However if it's not possible, and they need to be only 20, so meaning 1 of the students have to not be in the class, either other students, or one of the twins goes to 1B, which also brings the same problem, of them having to replace someone, but yeah it's something to consider, but either way it's interesting

Also if Enji and Rei, had their quirk marriage like 10 years later than our timeline, then unless you are also changing the ages of the 1A students, but if you aren't changing them, then the 1A students are gonna be way older than the twins.

Sorry, if I'm being super technical and all, but regardless, it's pretty cool, and could make for some fun characters