I have tried this very same combination - F12 + FreeBSD + KDE on Wayland and WiFi works to me out of the box (even during installation!), but a lot of things doesn’t work for me - suspend and resume doesn’t work at all (even when I blacklist WiFi kernel module - suspend starts working, but resume doesn’t). A lot of apps on KDE also crash for me - every time I try to run Konqueror or Falkon they crash immediately).