If you duplicate the programming, say encoder 4 and encoder 6 to use the same simple .easypar command. then then they will stay in sync. You can try this and watch the Led ring on encoder 6 track the movements of encoder 4.
So you can have encoder 4 and the same physical encoder on the next group - encoder 12 - matching and as you swap groups the value of the physical encoder will stay the same. You can have all 4 the same - encoder 4, encoder 12, encoder 20 and encoder 28.
BUT this only works within the same preset.
The only way to do what you really want is to write a program.
You set up all the controls on the BC to output different midi messages, say CC, and the program reads these and outputs something else.
The program creates virtual BC 'pages' - as many as you like.
You can use whatever buttons you like to select 'pages' of encoders as the program uses the BC button message to keep track of which page it is on and varies the encoder translation.
(the BC never really changes encoder group or preset)
When you change 'pages' the program sends the values for that 'page' back to the BC to keep it in sync.
I use this method for a Yamaha 4-op synth controller (TQ5) to swap between the 4 ops.
BCR<=>TQ5and
Al the best
Royce