MrMarcello
In a well-ordered universe...
OK fair enough, kudos to you for actually coming up with an alternative (most of the folks on here raging about that seem to have no idea about an alternative and just want to rant).
Having said that, your suggestions mean quite a huge shift in the way we play, when was the last time we played 3-5-2? Or AWB in midfield? We already have a big issue with players not being comfortable in their roles due to injuries and the lack of consistency that allows, adopting an entirely unfamiliar system mid match would only exacerbate that.
Hence why I tossed suggestions out there but no one responded, partly because threads refresh too quickly that posts get lost in thread counts and partly because most don't have suggestions just moans.
Personally, considering Dalot did push into midfield some (see link) until he swapped to RB very late, pushing him to RCM with Eriksen to LCM, and subbing Reguilon at LB for Mainoo (only if injured of course) would probably have kept the shape and tactics but more importantly would have kept some balance and control in the side. Other alternative might be AWB to RCM with Dalot and Reguilon at FB to get some attacking width.
Either AWB or Dalot would surely provide more defensive awareness in the midfield role in an emergency but it's possible they get pulled out not having a true feel for the position. I don't think either would have been left wandering about if assigned to be a holding mid alongside Eriksen. I also feel Antony should have been pulled off at halftime, pushed Rashford and Garnacho applicably, and possibly tossed Amad or even McT up top.
https://onefootball.com/en/news/nottingham-forest-2-1-manchester-united-player-ratings-38801294