Change MIDI channel for project track using CC121 button

I don’t have a CC121 but would like to somehow change the MIDI channel via key command if possible. “Toggle MIDI Input” doesn’t seem to do anything for me and I have several MIDI inputs. I don’t see what would be toggled. I have tried this keyboard shortcut in the Project window and in the mixer, with it assigned to a key on the MCU (Mackie Control Universal) and as a shortcut.

This seems to be the only post about that command on this forum. What is it suppose to do?