Could see Tuchel moving us to a 343
Onana
Dalot - Tobido - Martinez
Frimpong - Mainoo - Neves - Maatsen
Bruno - Garnacho
Hojlund
I said similar about Ruben Amorim in the transfer tweets thread.
Option 1 - 3-4-3
People will see Maguire or Varane in the middle of back three and be concerned. But Sporting have had Sebastian Coates there who isn't quick. He is flanked by Diomande and Inacio who cover for his lack of pace and you want the central one to be aerially dominant. And Bruno in Central Midfield seems really bold but Sporting have played Pedro Goncalves there against weaker teams and the point of 3 CB's is to cover for a softer central midfield. This is your attacking formation at home.
---------------------------- Onana ----------------------------
--------- Diomande -- Maguire -- Martinez -----
--- Dalot ----- Bruno ----- Mainoo ----- Shaw-----
----Garnacho ------- Hojlund ------Rashford------
Option 2 - 3-4-1-2 or 3-4-2-1
This option allows your to play a more traditional central midfielder alongside Mainoo for defensive help. Personally, I'd go with the 3-4-1-2 as that allows you to get Garnacho alongside Hojlund so you have two quick forwards to find.
---------------------------- Onana ----------------------------
--------- Diomande -- Maguire -- Martinez -----
--- Dalot --- New CM --- Mainoo ----- Shaw-----
-------------------- Bruno -- Mount -----------------------
--------------------------- Hojlund ---------------------------
---------------------------- Onana ----------------------------
--------- Diomande -- Maguire -- Martinez -----
--- Dalot --- New CM --- Mainoo ----- Shaw-----
---------------------------- Bruno -----------------------------
-----------------Garnacho --- Hojlund ------------------