The two sides played out a dismal scoreless draw in the final Manchester derby of the season.
Fernandes, 30, who was named player of the match, heaped praise on De Bruyne, 33, who recently announced he would be leaving Man City at the end of the season.
"De Bruyne made the Premier League better," the Man United ace told Sky Sports. "If City is where he is, and Man United hasn't won many trophies in this in this period it's because of Kevin De Bruyne, and he deserves all the credit.
"He's done fantastic. 10 years in the Premier League is a lot. They have decided to part ways. I don't know from which side, but Kevin keeps being world-class, and it was a pleasure to watch him so close. It was a pleasure to play against him. He's gonna stay in the history of the Premier League, not only of Man City."