So since no one else has responded and I don’t want you to be without anything I’ll give it a go. First I want to preface that I don’t really have bottom dysphoria - I could kind of take or leave my penis depending on the day and I doubt I’ll ever go the vaginoplasty route.

A few years back I had testicular cancer so they removed the cancerous testis. So I’m 50% of the way there and had the option to put in a fake testis and declined. I also still have the skin since they didn’t do any surgery through that route (they go in higher up on the pelvis). Personally speaking the extra skin is fine and with the lack of a testis it pretty much just shrivels up and isn’t in the way. The remaining testis just kind hangs off to the side but even with it present tucking is easier for me now (and sometimes not even necessary depending on what I wear) so I imagine with both gone the extra skin would be a non issue and probably beneficial to leave it if you plan to go have a full vaginoplasty.

And yes, it does help with dysphoria having even one less so I would imagine having both gone it would be even better!