Mouse module advanced doesn't have drop down box to pick between acceleration modes (Adaptive, Flat, None) like it does under Plasma Xorg session. Furthermore, Plasma Wayland session resets the acceleration mode to Adaptive - observable in mouse UI under Xorg session by the setting being flipped back to Adaptive. Arch Linux Qt 5.10.1 Plasma 5.12.1
I have just checked on my laptop with Plasma Wayland 5.21.2 and the acceleration profiles are listed as Flat or Adaptive. Can you please check and confirm, thank you. I've set this bug to NEEDSINFO. When you reply, please change the bug back to REPORTED so we know it's ready for investigation or RESOLVED/WORKSFORME if the issue is now resolved.
Checked and confirmed.