Oh, excellent, that worked! I lose a footswitch because I use the same preset on my HX Stomp and HX Stomp XL, but I can live with that.
Now I can "simply" reload the preset via Midi, thanks for the tip, @enjalt, @Schmalle!
Btw: you can of course also assign the preset button to one of the expansion slots, i.e. footswitch 4 and 5 on the HX Stomp, or 7 and 8 on the HX Stomp XL, so you wouldn't lose a footswitch on the device!