Zenitsu and Midoriya would be cowering and crying in the corner while Bakugo and Inosuke beat them up and Sanemi, Iguro, Shinso, Present Mike, Kaminari, and Sero cheering them on and Tomioka, Aizawa, Sabito, and Urokodaki would just be standing watching their entertainment silently and doing nothing to stop it
Uzui, Rengoku, and Kirishima would literally be besties
Kanao, Aoi, Nezuko, Mitsuri, and all of the MHA girls would be hanging out
Mirio, Todoroki, Iida, Tanjiro, and Muichiro would just be talking
Though I think it would be chaos