Mount has been sidelined for four games with a muscle problem but returned to first-team training this week before skipping the Champions League trip to Bayern Munich, which United lost 4-3.
Varane has missed the last three games, all of which were defeats, after being forced off against Nottingham Forest, and has joined Mount with the group in recent days.
Ambrabat is yet to make his debut after joining on deadline day three weeks ago, but is also in contention this weekend following a back problem. Harry Maguire will also be assessed after a knock.
“As you say, Harry Maguire but we will see again after training,” United boss Erik ten Hag said on Friday.
“But Varane will train, we will see, Amrabat will train, we will see and Mount as well. But they didn’t play for short or longer-term. Varane, obviously, was the shortest out.”
United remain without a host of other players including Aaron Wan-Bissaka, Luke Shaw, Tyrell Malacia, Tom Heaton, Amad Diallo and Kobbie Mainoo. Jadon Sancho and Antony are still unavailable for selection.