I think you guys are trying to make the second step before the first. Worldclass players/talents aren't going to sign for you in your current situation. Why would someone like Sancho, Joao Felix, Griezmann, Dybala etc. go to United if the whole world is in for them?
First, you need to prove the world that you're on the right track. Sign young and promising players, play a specific brand of football, build something over the course of multiple seasons. Are you doing that? I'm still not sure. Solskjaer could be a coach with a clear idea of how he wants to play, but he could also be a typical traditional/outdated British coach.
You need to be aware of the impression you currently leave around the world. Your club has no philosophy, it doesn't seem like there's an overarching plan or anything, and you're obsessed with individual quality/convinced that your problems can be solved by just signing better players. And willing to massively overspend as long as the player is either English, plays in the EPL or has some sort of history with your club. To me, you're like the prototype of a club living in the past.
feck signing the very best players. That's not how exemplarily Liverpool managed to get back on the top, exemplarily. Go the long way, do your homework and assure that the basics are there. Make it clear that you're vuilding something coherent, signing players that fit to a certain style of play, even if they aren't the very best in their respective positions. Money alone isn't enough anymore and if it is you automatically attract players who come for the wrong reasons. You need to become attractive again for athletic reasons, not monetary ones.
I'm still not sure the leaders of the club or your fans have understood that. You sign Harry Maguire for 90 fecking million and everyone's happy again.