Nah, we need some hope around here. Let's assume he's a star.
Updated long-term depth chart:
ST: Hojlund, New #9
LW: Rashford, Garnacho
RW: Antony, Diallo
#10: Bruno, Mount
#8: CM1, CM2
#6: Mainoo, DM2
LB: Shaw, Malacia/Reguilon
RB: Dalot, Wan-Bissaka
LCB: Lisandro, LCB2
RCB: RCB1, Maguire
GK: Onana, GK2/Bayindir
Squad: 3rd striker (Hugill?), Pellistri, Mejbri, Alvaro, Lindelof/Evans, 3rd keeper.
No idea if Bayindir is good enough, so just the 6 signings, not counting a 3rd striker (literally anyone with a pulse on a free) and 3rd keeper. Maybe down to 5 if Casemiro stays for one more year.
Sell/stop paying:
Sancho, Martial, Eriksen, McTominay, Eriksen, Varane, one of the backup LBs.
Probably impossible to sign 3 midfielders though, so maybe one final year of Casemiro and sign 2 quality midfielders, one who can sit and pass as a #6 and a physical box to box #8 who can do a bit of everything.
4 backup signings (#9, LCB2, CM2, DM1) should be affordable (say 30M per spot with a bit higher at striker and a bit lower for one of the midfielders) and then 3 massive signings (RCB1, CM1) more like 70M per, so 260M spent but maybe 60M recouped in fees from McTominay, Sancho and Van De Beek for a 200M summer.