Using an external foot switch to toggle position in presets

Hi there

Hoping someone can help me with something I haven’t been able to figure out. I have an external footswitch with two switches on it. It works fine with my MC3.

What I want to do is use it to toggle between Position 1 and Position 2 of any given preset that has toggle mode turned on. All I can think of is to replicate an entire preset on the external footswitch, and it will behave the same - say copy Preset A into Preset D, and then the external switch ‘D’ will do the same thing as Preset A, including toggle between positions. But that seems a bit limiting.

I’ve also looked at the ‘Fixed Switch Custom’ mode - but that doesn’t have an option to toggle between positions.

Is there a way to assign the footswitch so it universally switches between Position 1 and Position 2 in whatever preset is currently active?

Any help would be greatly appreciated!