I think this Liverpool squad is suited to a back 3 (or at least a narrow formation like the diamond), that way they can play Frimpong and Kerkez as wing backs and also have all their big names in central areas. Something like:
---------------------Isak/Ekitike----
----------------Wirtz------Salah
Kerkez--Mac Allister------Gravenberch---Frimpong
--------Van Dijk------Kounate-----Gomez
----------------------Alison
*or Szoboszlai
I think this will resolve most of the issues they have had, namely at FB and also Wirtz playing as part of a midfield 3. He's more of a forward than a CM (unlike Ode for example), so they end up with a 4-2-4. He therefore poses similar tactical issues like Ozil, Germany decided to play him out wide in the world cup just like Mourinho did in the big games.
The brilliant thing is, they don't have enough CBs to switch to a different system. The should have wrapped up the Guelhi deal way before the deadline day. Still, I think they will eventually figure it out but it might be too late for the title. Isak will get fitter and sharper, the same applies to Mac Allister who is the one that controls their game from midfield (which they have been lacking).