HOW TO POSITION 2 PAIRS OF SPEAKER FOR ALTERNATE LISTENING

Oh, wolfie, you are a bad man...

@infinity_audio 
I think you are just going to have to accept that there will be some interaction with the adjacent speaker. But, then everything in the room will contribute to affecting sound reproduction.
If it were me, I would try to set up each pair as best as possible and not concern myself with any interactions. You can only do so much...
Bob

Did you try reversing positions?
Do all the permutations, if possible.
B

As I said, perhaps you should make the best of the situation and give each pair of speakers the best possible placement and let it go from there.