De Gea's contract with Man United has officially ended. And currently, de Gea is a free agent. Yes, Man United did not renew the MU goalkeeper's contract for several reasons. However, because he is currently a free agent, Man United can actually re-sign a contract with him. But I don't think this will be done by them. Moreover, they are currently eyeing several good and quite young goalkeepers like CostaCosta, David Raya and others
Man Utd is keeping De Gea pending simply because they are hoping they can seal the deal on Onana from Inter. If it isn't successful, they might recall him back to the squad. De Gea has had a good run with Man Utd. I personally believe it's time for him to set sights somewhere else - probably in a different league other than Premier League and see the rest of his career there. Even Man Utd fans especially the ones I know personally wanted him gone 2-3 seasons ago.
I think Onana deal will be sealed in few days to come obviously the chances of DeGea retaining his first position at Man Utd is slim if Man Utd eventually signed Onana because one of his attribute is in his ability to use both feet with the ball as well as pressing the ball with the defenders which DeGea lack, experience goalkeepers are expected to use the ball very well and start their attack right from goalkeeping area, though DeGea had so far proven to be a very brilliant goalkeeper, however with the high standard and quality in the league Man Utd is trying to improve on that area on their squad which their arch rival Man City had an edge over them with regards to Ederson who is a all round brilliant goalkeeper.