if you browse the seke tag here, there's tons where the couples switch roles
There's a lot of this sort of thing in the Shingeki no Kyojin doujinshis. The Levi character is very small and very butch, pretty rude, too. god I love that character. LOL. He makes a very cute top there's a lot of Levi/Erin dj if you're interested.
for the height difference one:
http://www.mangago.zone/read-manga/baby_i_love_you/
http://www.mangago.zone/read-manga/otona_keikenchi/
http://www.mangago.zone/read-manga/ore_no_ushiro_ni_tatsu_na/
http://www.mangago.zone/read-manga/uchi_no_tenshi_ga_kemono_deshita/
http://www.mangago.zone/read-manga/konya_mo_nemurenai/ and sequel: http://www.mangago.zone/read-manga/kimi_to_kore_kara/
http://www.mangago.zone/read-manga/scratch_blue/
Love Stage also have a reversal sex scene near the end!
and this list can lso help u http://www.mangago.zone/home/mangalist/45879/
How is that a weird question?, See I'm one of the biggest promoter of that trope in this site so you better go and ransack my list and stuff.
http://www.mangago.zone/people/listtag/49344/uke/
I have a kind of weird question lol, but does anyone know of any yaoi where the uke tops the seme? Or a height difference where the top is smaller than the bottom?? xD