Line 6 - The HX Stomp XL processor's Command Center functionality, MIDI capabilities, and external expression pedal jack make it an ideal master controller for your entire setup. Learn more: https://line6.com/hx-stomp-xl/
Evening Sun MC6: DIY Midi Controller for HX Stomp (and others) - Helix - Line 6 Community
HX Stomp with MC6 MIDI Controller Part 2: Advanced Features - YouTube