Create loopback devices in PipeWire. More information: https://gitlab.freedesktop.org/pipewire/pipewire/-/wikis/Virtual-Devices.
pw-loopback
pw-loopback -m '[FL FR]' --capture-props='media.class=Audio/Sink'
pw-loopback -m '[FL FR]' --playback-props='media.class=Audio/Source'
pw-loopback -m '[FL FR]' --capture-props='media.class=Audio/Sink' --playback-props='media.class=Audio/Source'
pw-loopback --capture-props='media.class=Audio/Sink audio.position=[FL FR]' --playback-props='audio.position=[FR FL]'
pw-loopback --capture-props='audio.position=[FR FL]' --playback-props='media.class=Audio/Source audio.position=[FL FR]'