I don't get it, where's the problem, you just stated that it's flexible with many pairings.The problem is the CB pairings, if you’re playing to their strengths, are:
Stones/Dias RCB
Laporte/Ake LCB
If you play Stones and Dias, you move Dias to LCB.
If you play Laporte, you can pick and choose between Stones & Dias, which is what has happened the last few games.
I expect Stones & Ake to be playing in the Cup next week!