This should work for all Nvidia user working with Plasma6 on Arch, Garuda etc:
Edit /etc/mkinitcpio.conf
MODULES=()
Change the Line and add the Nvidia Modules:
MODULES=(nvidia nvidia_modeset nvidia_uvm nvidia_drm)
Save the File and create the initramfs:
sudo mkinitcpio -P
Now Add the Kernelflags to Grub: nano /etc/default/grub
There is a line like this:
GRUB_CMDLINE_LINUX_DEFAULT="loglevel=3 quiet"
add this to the line:
GRUB_CMDLINE_LINUX_DEFAULT="loglevel=3 quiet nvidia_drm.modeset=1"
Now generate the new Grub config:
sudo grub-mkconfig -o /boot/grub/grub.cfg
Reboot and have fun with wayland. Maybe you have to install: xorg-xwayland