It looks like SWH “Matrix: MS to Stereo” is the standard mid/side decoder matrix plugin. It seems to require the left input be the mid, so I’m wondering about options for the occasions when I forget this (e.g. the first time I tried it). Is there an easy way to swap L and R on a stereo track? Are there any routing options going into either plugin stack?
This is one of the reasons that a node based effects interface would be “a good thing”.
For now, set up an om session where you can wire the channels by hand and then set it up as an insert.