I was thinking about this very feature this week.
I'm having difficulty when I switch from my Mac (CMD+) modifiers to my phone Android (CTRL+) modifiers.
This would be super useful for specific app.. ex. Chrome Shortcuts.. Vim bindings.. etc..
A simple way to "toggle" between multiple mappings.. have it as a Reserved Chord - https://twiddler.tekgear.com/doc/doku.php?id=specialchords
Such that something line N+S+A 000M.. etc.. where you can now have up to 102 different mappings!
N+S+A 000R, N+S+A 000M, N+S+A 000L etc...
The chord N+S+A (or any 3 modifier combination) is a 'difficult' one to do.. and could require two hands, so it won't get accidentally triggered.
All you would need is a slight buzz from the haptic feedback the the mappings changed successully.
To know which mapping is currently active. Have a chord similar to N+S 0M00 (that prints out battery) to print out the mapping name. And another one to print out a list of available mappings.
The *.cfg file name would indicate the mapping to the chord. By filename.. similar to what it is now. the Twiddler.cfg is the mapping. the filename. Something like - Twiddler-000M.cfg.
I don't know if the 'name' of the mapping is already encoded in the .cfg file.