ilovefuzz.com

Maybe a rotary knob that allows you to select which output it's on. Seems simple and DIY'able enough.

I know mark from make sounds loudly has made a couple

You could hit up Copilot's Adam. You looking for some of those fancy tapers or just something that gives you more expression outs?

I learned recently that you can just build a passive splitter box and it works fine. Split one expression pedal among as many expression outputs as you need. you just need trs/stereo jacks.

That's what I'm looking to do.

But I want a rotary to select between 3 outputs (1,2,3,1&2,1&3,2&3, or all 3). And then two stomp switches. One for selecting between a fixed momentary knob or the expression pedal.