If Ronaldo leaves and the current rumored players come in (Eriksen, de Jong, Martinez), i would guess we do this:
Sancho Rashford Bruno
Frenkie Eriksen McTominay
Malacia Martinez Varane Dalot
De Gea
Garnacho Martial Elanga
Van de Beek Fred Hannibal
Shaw Maguire Lindelof AWB
Heaton
My guess is Bruno gets placed wide and we use Rashford/Martial through the middle and being first backup for front 3. Garnacho and Elanga would get a lot more game time. It probably suits Ten Hag more to pick from these rather than shoe horn Ronaldo, we'd press better as a team and probably play better, but the goals would obviously need to be spread out and there really isn't enough goals in that group.
Basically .. let's hope Ten Hag can work magic with Martial