We already have bindings for Oculus, Index, Pico and Cosmos.

Others will have to be created, if you do please send them to us so we can add them as defaults in future versions. Below here you have the Oculus bindings as reference

leftmenubuttonpressed

the leftmenubuttonpressed action is required to bind but is not actually used. You can bind it to anything you want. On SteamVR, opening the menu is currently hardcoded to open with left secondary button. We'll work on keybinding improvements.

Pose button doesn't exist?

When editing the bindings go to another app, click poses then go back to Breachers and it appears

Reference