There's a cracking write up in The Athletic about how the re-build has to continue in the summer.
But having lost Kolasinac, Mustafi, Sokratis, and Ozil this window, I think we'll sell/move on Torreira, Guendouzi, AMN, Nketiah, Nelson, Elneny, Mavropanos and Chambers in the summer and hopefully not extend Luiz while Ceballos & Odegaard will go back to RM, and Ryan likely back to Brighton.
We would still have this squad:
Forwards: Auba, Martinelli, Saka, Pepe, Willian
Midfield: Xhaka, Partey, Willock, ESR
Defenders: Gabriel, Holding, Saliba, Mari, Bellerin, Tierney, Soares
GK: Leno & Runnarson
Ignoring other U23's who might come through the ranks, I think you'd want one more striker or wide man depending on how Martinelli plays, 2 more midfielders, a LB, and a back up GK.
You'd think given the funds we could raise £50m in transfer fees plus + £2-3m per week in wages we'd be able to fund some good up and coming players in the 20-24 age profile.
It would be a huge amount of churn but it's the level of reform Emery never got but is totally needed with this squad.
Oh, and I think we can afford to go to a leaner squad (albeit the one I proposed is made up of 23 players) next season as you'd hope scheduling is kinder.