This one: https://www.mangago.me/read-manga/like_a_tidal_wave_from_pheromone_shower/
This one too: https://www.mangago.me/read-manga/playtime_with_hakdo/
If you’re good with manga: https://www.mangago.me/read-manga/neko_x_neko/ (this is probably the one that got me into switches in the first place)
There are more out there if you loosen your standards a bit or are cool with just a single scene. It’s really underused as a trope and it kills me.

I’m superrrrr into switches and they barely exist anywhere. Eunho please either give him a genuine serious reason you’re against it or give in to make Rak-hyun happy (I will also be very happy).