Who ends up in 1a/1b in Let me be the mastermind?
1-A; class roster is the same, with the exception of Izuku not being in it. Instead we've got a Shinso who actually did shit like physical fitness before getting to UA (guys he was a noodle, it's highly unlikely he did any real non-Quirk related training pre-SF. He's at middle-school Izuku levels of noodle then) so he was able to actually find a means of dealing with the robots, plus got rescue points helping Uraraka.
1-B; class roster is changed in that Neito isn't in it but Inasa is, and that Jozu is a regular student rather than a recommended. While Inasa and Shouto didn't have a great interaction during the recommended exam it still went better than canon so Inasa decided to attend UA.
Izuku and Neito are in the same homeroom for Management. Snipe is their teacher.