Every omegaverse is literally a different universe with its own set of rules for how the sexes work. I think that's what I like most about them is the fact that you learn the "rules" along the way.
But honestly, if we're going to go logically, being repulsed by something doesn't necessarily mean you can't do it and won't enjoy it. Just like a straight guy can like anal even if its not with another guy. Some straight guys like to be fucked by their girlfriends with strap-ons and other toys.
I've seen irl some homophobe straight guys totally turning bi because they had a good experience I've also seen straight men just totally avoid butt stuff even when its the other partner taking it.
Normal people can smell pheromones too! Especially that of their partner. It your partner smells good to you when they're at their sweatiest/unwashed, then its likely that your immune systems are compatible and will have good offspring lol That's why smelling your family when they're all sweaty is the grossest thing ever. They smell raunchy and gross af because you're not supposed to match up with them. That repulsion is how I understand some alphas and omegas not liking each other at all.
Depends on what you read every omegaverse is different you should check out “A tough alpha wants to be loved”
There are no canon rules to an omegaverse, if the author decides to do something else with the universe, it can be just that
Not trying to bring down the mood or what not, but since ML is an Alpha and a dominant one at that, shouldn’t him getting fucked in the ass be damn near impossible, and not only that but excruciating for him to experience? I imagine the latter being how an omega’s d!ck would be completely useless if they were in heat and someone tried to get fucked by them? Idk I’m just thinking like logically with the “rules” of the verse since biologically he’s not meant to do that. And with him being a beta who can experience/smell his pheromones, just going off of other omegaverse stuff, shouldn’t he also be repulsed/not able to withstand the pheromones of a dominant alpha? ╮(￣▽￣)╭