This one is a funny story, both like bottoming, so they switch to help each other:
https://www.mangago.me/read-manga/happy_shitty_life/
This one shows them switching in some +18 side stories... i don't remember if they've switched up till now in the main story (that's called Take Off)
https://www.mangago.me/read-manga/camping/
This one i haven't read it yet, but i saw a lot of recommendations for it, so i guess is good hehe
https://www.mangago.me/read-manga/playtime_with_hakdo/

I want to read a Bl where they’re a switch I feel like it’s so uncommon to see. Please help!