TRS junction boxes / AB pedals for expression pedals?

Beef

Is this even a viable idea, and if so anyone know where I can find one of these around here? Something like this is exactly what I'm looking for, but I wonder if there any alternatives that are closer to home.

My expression pedal ends up being hogged by one pedal most of the time, despite having a growing selection that'd be drastically enhanced with the added modulation. Can't be arsed fiddling around swapping out cables and all that. Would love a way to route 2 or more EXP outs into an A/B box, so I could just flick between pedal/exp combos on the fly with a simple footswitch. It'd actually be a total game changer. 

But I wonder if you might run into issues with the pedals that have their exp jacks connected but aren't in use at that time. Only have one working TRS cable at the mo though so I can't even test that. I'm imagining that it'd probably be a more widely available pedal already if there weren't some serious drawbacks and flaws in the design.