We tried it at Stamford Bridge. Put Eriksen at #10 and pushed Bruno wide. The experiment didn't even last half an hour. Ten Hag ended up subbing Eriksen, putting Bruno back down the middle and putting McFred on so we could compete.
Its not that Eriksen is a bad player. Its that the puzzle pieces we have to play the way we do, simply don't suit the way Eriksen plays at #10. That should come as no shock to anyone who remembers Eriksen playing wide of Dele Alli for Pochettino's Spurs. The Premier League is a physical league and, often, the team that runs most wins out. Eriksen's game has never been based on engine. Conte converted him into a deeper midfielder at Inter, partly for this reason.
What United need, what we haven't had for the best part of 10 years, is similar profiles of player in every position so they are interchangeable. Our whole system shouldn't be dependent on certain players being fit, especially having spent £1 billion since Sir Alex retires. Yet it is. If Antony is injured we have no inside right. If Varane is injured we have no pace at centre back that can cover runs in behind. If Eriksen isn't available we can't move the ball forward from deep in midfield...
...and if Bruno is unavailable we have nobody at #10 who has the stamina to get through the work that he does in and out of possession. Our squad remains significantly imbalanced. Hence why certain players are so vital to us. Take them out and the whole thing needs reshaping simply to get a positive level of output.