Hello,
You can control multiple parameters with one control using either an expression pedal or a MIDI controller. Since you have 3 stompboxes that you’d like to control this way, I would suggest a MIDI controller that would allow you to control all 3 stompboxes.
The user manual explains how to configure these settings (Exp pedal page 26, MIDI page 44)
https://s3.amazonaws.com/com.eventide.downloads/Product+Manuals/SpaceManual.pdf
