After doing a successful test of adaptative opacity with a intel GPU on wayland , i made a try with my nvidia hardware (eglstreams) and got two issues : 1)the panel opacity option menu has disappeared. 2)panel and panel widgets have no transparency. I have no transparency issue with kwin and the desktop in general. The issue affects only the panel and its widgets. no errors related in journalctl. Sorry for may english.
Opacity issues should be fixed in 5.23.