I can't remember the title but it's omegaverse, school setting, AxA, because the MC is an Omega that turns to sss-class Alpha. I remember ML being a delinquent and because he's just A+ or S-ranked he ends up being shou.
https://www.novelupdates.com/series/after-i-turned-from-o-to-a-i-became-the-national-male-god/ this one probably