While you changed the question, reading through the comments I can guess at the original wording. I understand, I came to American comics directly after Japanese manga. So when I first got into SteveTony I tried to wrap my mind around one being a 'seme' and the other an 'uke'. It didn't really work since neither truly fit either grouping, and I defaulted to Steve being 'seme' and Tony 'uke'.
After getting really into the fandom, really reading the comics, watching the movies, I started to realize that they didn't fit that titling. It opened my eyes to more characterizations of homosexual (and really pairings in general since yaoi, like someone mentioned, is basically a super feminization of one character). So these days I like Bottom!Steve just as much as I like Bottom!Tony.

I also like BottomFromTheTop!Steve/TopFromTheBottom!Tony, I like D/S and can see both in either position, there's a lot of different ways to look at them and I think I like them all.