As of the latest VRChat update [2021.3.2][1121] the "VRChat Configuration Window" cannot be opened anymore and this was the only way to rebind joystick inputs (as far as I know).

Unity blog post explaining the situation

"Display Resolution Dialog aka. Screen Selector has been disabled by default since 2019.3"

I've tried adding command line argument "-show-screen-selector" but the configuration window still doesn't appear.

My Udon Vehicles heavily rely on the ability to bind steering wheel setups to existing input axes in VRChat and as of now I don't know any way to do this anymore.