Responses
Mika Sadahiro's mangas have a lot of seke (top and bottom) characters. Also, Dog Style, Haru wo Daiteita.
they are called seke and are pretty rare, none come to mind at the moment, but maybe you can search by tags ╮(￣▽￣)╭
Here is my list with couples that swich roles
http://www.mangago.zone/home/mangalist/68441/
There are some more if you serch for tag seke, but they are mostly about guys changing roles depending on the partner
Ive been searching and searching - because I am bored by "only bottom" or "only top" guys - any suggestions?