With a focus on United I will go...
Marcus Rashford - averages about 10 PL goals a season, poor decision-making, average ball retention, average finishing, no left foot, average in the air. Definitely a “good” player but nowhere near a “great” player for me.
Edwin van der Sar - saw this mentioned above and funnily enough was having the same conversation with a mate when he was linked with the Sporting Director role. Best years noticeably behind him by the time he joined Utd. Was solid but no more than that in my opinion.
Evra - This will be controversial but for me, Evra was the weak-link in our back four defensively for years. Decent going forward but his average delivery rather ruined his direct running and pace. Positional play as a defender was never that good in my opinion. I think if he was scrutinised like modern players are scrutinised this would get highlighted more. At one time it was noticeable a large portion of the goals we conceded came down his side.
Have to caveat all of the above by saying that we’re talking about “players I don’t rate as highly as others”. I’m not saying these players are poor, I’m just saying they are generally overrated by popular opinion for me.