What kills me is that I'm going to have to learn half of the skills to do this sort of thing just to reverse one PC's stereo channels. (Though in all fairness maybe it only seems complicated because this is my first contact with Suse/Tumbleweed.)
easyeffects has a filter just for that and you select RL
That filter wasn't included with the default package I tried. Maybe I used the wrong package manager, TBD when I have time.
Edit: I switched the machine to Manjaro from Tumbleweed (for several reasons) and it was easy to do w/ Easy Effects at that point.