Hello,
Unfortunately, as outlined in this wiki post, the graphical applications in MRtrix won’t work easily within WSL/WSL2. There isn’t much we can do about this currently, although this may change once Microsoft adds Wayland support to WSL2. It’s in the works, but not yet released – I’m hoping it won’t be long, at which point we’ll likely switch from to WSL2 as our recommended installation option on Windows (currently, we only support installation under MSYS2, since that’s the only way to get mrview to work reliably).