Oculus CV1 VR setup for archviz

Hi guys!
How to create two modes VR and desktop in a single archviz application?
Currently I’m using a simple character (FPS) with controls by keyboard+mouse. I want to add the option of enabling VR mode (Oculus CV1, only head rotation + controls by keyboard+mouse (with Y-axis blocking)) by hit a key or activate HMD.
I’ve tried running ExecuteConsolecommand stereo ON but it did‘t work.
Is such an improvement possible in one application (in one level)?
Are there any tutorials on this issue or maybe examples of blueprints?