Question about headphone monitoring between two decks [Traktor Pro 2 & Denon MC3000]

On my CDJ days I had a Gemini Executioner mixer. I learned to use that and I'd like to have the following function work on Traktor:

On the Gemini mixer changing what I hear on headphones was done by turning a knob from left to right and volume was balanced between A and B decks. There was no need for cue buttons because both channels were "automatically" controllable. I found that intuitive.

At least at the moment I have no use for more than two decks and I'd like to have the Cue-Master knob to balance the volume between A+B decks. I feel I shouldn't need those Cue buttons at all.

Am I missing something and there is a simple solution, or should I map (how?) that described behaviour? My controller is Denon MC3000.