Until now I have not seen any new players that Manchester United are targeting, whether they are working in silence or are they still looking for players if they really need it. They have to act fast for the transfer market because if they slow down, they could lose the players they want because they lose quickly to other clubs.
I haven't heard any transfer news other than De Jong, actually they are moving quite slowly. Currently, many teams have taken action to make transfers, but Manchester does not seem to be working on this situation.
They wanted to get Darwin Nunez but they couldn't get him either and Liverpool did. Let's see what kind of names they are interested in in the coming days

Apart from the news about de jong, we haven't heard of any other players that Manchester is targeting, indeed Manchester has approached several players before but it seems it's just an rumors without a definite approach from Manchester, Manchester passive movement in the current transfer market might cause a little panic from the fans about their squad next season, especially now that Manchester United has released 11 players such as Juan Mata, Pogba Lindgard and Cavani.