@ziddan I use my own diy shoes for locomotion.
With my shoes i can walk and run in place or walk accross my room , to move foreward. Then i have pressure sensors to move sideways and backwards, standing in 1 location, but i can still move around in room scale if i want.
The problem of the idea you mentioned (and mine too) , is that you have to be able to inject the sensors into steamvr with a steamvr driver or be able to unlock the key binding of mouse /keyboard or else to any button of our vr controllers.
Unfortunately , no vr developer have worked on fixing the openvr input emulator after 1 old steamvr update from valve that screwed the openvr input emulator key binding.
So your idea is not possible for games that only support vr controller and not keysteokes or gamepad, unless you get someone have your sensors of preference work in steamvr