It’s actually pretty easy to program the FMS in VR… I like to use the laser pointer to just type away on the keypad… after a few times, it gets to be like second nature. I have a quick video showing how I have the Quest controller set up so that it’s easy to work with the knobs (increase/decrease) and also the push/pull knob interactions for the systems that have knobs that turn and also push (or pull, in the case of Airbus).
I never use the mouse anymore in VR. In fact, the mouse is across my office on my desk and far away from the VR setup 
If you are interested, here’s the quick video showing how to set up the Quest controller. It should work for other VR controllers, too.
