On the Egnater modules, there are relays I think that do the switching.
I think I read that Jeff Hilligan can modify the modules so that it selects channel B instead of A in a single channel setup...which leads me to believe that maybe it's possible to put in a toggle at least to select between the two sides of an Egnater module when used in a single channel RM4 or RM unit?
If that's possible, maybe instead of a toggle, a 1/4" (or 1/8" jack) could be added to allow for midi switching via GCX or even a G-Major to get to both channels of an Egnater module. I have an RM100 with a G-Major mounted in the chassis, I sure wouldn't mind a couple 1/8" cables running to some modded Egnater modules if it meant I could use both channels without modding my RM100 since that seems like a huge pain.