This is an add-on that receives motions sent by VMCProtocol. It previews, records them in real time in Blender. About VMCProtocol: https://protocol.vmc.info/
It can be used with VirtualMotionCapture to capture SteamVR motions.
https://vmc.info/
Currently, VirtualMotionCapture motion sending function is a paid feature (2021/11/16).
https://akira.fanbox.cc/