The Line 6 FBV Express Mk2 is a relatively well-known and affordable peripheral "stomp box" for changing guitar sound patches on a Line 6 POD controller. It communicates with the POD over ethernet but also works splendidly as an independent USB device. I can't recommend anything more highly than the Keith McMillen 12-Step for foot control, but I was curious to see how the FBVEM2 would spec out in this regard - and it works!
In the image above, you'll see the controller setup in the Line 6 FBV Control software.
In the attachment below, is my .kmmacros folder of macros - triggering simple notifications using the MIDI Controller Changes incoming from the device. Here, vol and wah sweep control only sends a notification when top-value 127 is hit with toe all the way down - this avoids singing a notification each time a new value is sent.
These are Single ("one shot") triggers, but Momentary and Toggle (toggle modes on/off etc) are also available for added functionality on the KM end.
Hope this helps or inspires.
fbv-express-mk2-triggers.kmmacros (161.6 KB)