About three years ago I worked on the game Hello Engineer. I have done more than two hundred concepts. Not all of what was done was included in the final release, as the concept of the game has changed a lot.
I actively used a VR helmet in my work (Oculus Rift S, Gravity Sketch). The technology is usual: I draw in a helmet, then I make an overpaint in Photoshop. At the output, we get a concept and a dummy for a 3d modeler.