Midi input binding

Hi there,
I’m working with MIDI to control various post-process parameters in Unreal.
I get the midi coming from my different midi controllers and set it as variables (like CC1, CC2, etc…).
I then use these variables to control parameters, like light rotation.
Everything is working correctly but i’d like to be able to reassign quickly the parameter i’m using for a specific post-process parameter (for instance changing from CC1 to CC2 the parameter that controls light rotation).
I’d like to make it work with the engine input binding using action mappings to make quick reassignments.
Is there a way to select blueprint variables in the engine input binding? Maybe this is not the way to go, and if not, what would be the best workaround?
Thanks for your help.

You can reach all vars and methods of BP that are public. But of course your first step - to reach BP itself.