Akanji should be the DM option alongside Rodri.
He's not strong enough as a central defender, certainly in the air, but he is quick enough and certainly has the passing technique to help us higher up.
I would than go Walker, Dias, Laporte and Ake as the back four until Stones is back.
I'd drop Mahrez for Kev wide right, have Walker doing the donkey work foil overlaps.
Gundo in the ten and Phil can decide if he wants to fight it out with Jack on the left for now.
...............Ederson........
Walker...Dias...Laporte...Ake
.........Akanji....Rodri.....
De Bruyne...Gundo....Grealish..
... ............Haaland.........
Strangely...I like the idea. Pep tried Stones at CDM at some point didn't he so he has previous.
I think the idea of Walker doing the legwork to create space for Kev is the bit I like most really. Even if Mahrez plays instead, giving him space in dangerous areas is a big plus too.