Here’s one way to do it. PITCH MIX holds an unusual position in this effect routing. The downside is that’s there’s a short processing time [running through the delays] that will impact your clean tone. 100% wet MIX; everything else at neutral or minimal values. KEY and SCALE don’t matter with PITCH values at UNISON.
Map PITCH MIX to the expression pedal at A10+B0 for heel, and A0+B10 at full toe. The image above shows the expression pedal parked at mid-throw [equal levels out to left & right].