All Might and Endeavor respectively become Sir Nighteye and Burnin's sidekicks.

After the battle of Kamino, Dabi didn't wait. The world already knows what a horrifying villain he is. And, there's no way he's going to let Endeavor become the Number One Hero for even a second. So, he records and posts the video of who he really is a day after it all goes down. Now, in the midst of this great scandal, the HPSC knew that they had to do something. They can't arrest Endeavor and not use his firepower and skills in some capacity nor did they want that man to be their Number One Hero. So, since they have connections to some of Endeavor's serious investments, they do the following: give Burnin a serious promotion, making her the face of the agency, while Endeavor is forced to step back and work for her as a sidekick.

At the exact same time, All Might may not be able to use One for All anymore, but he knows how fragile he left Japan in his absence. He can't give up. He has to do something! Which means he needs to relearn the basics, learn to fight Quirkless. He's too embarrassed to ask his student Izuku to do this nor any of his fellow staff. So, instead, he reaches out to Sir Nighteye, wanting to fight alongside him again. At first, Nighteye refuses, not wanting Toshinori to keep fighting like before, but upon realizing that the hero still has the same recklessness, he decides to do it, now using it as a ploy to show Toshinori that he knows best and keep an eye on him. Maybe get him closer to Mirio so that One for All can go to him instead of Izuku Midoriya...