The Ivorian appeared set for a loan move to Parma until the Premier League club swooped in at the 11th hour to complete a permanent deal, with hours remaining in the transfer window.
According to the Guardian, the Red Devils will pay Atalanta €30 million up front, whilst the agreement also includes a series of add-ons.
However, delays in attaining a work permit in the United Kingdom mean that Traore will remain in Italy until January and will remain available for selection for Atalanta.
The winger has been included in all three of La Dea’s matchday squads so far in Serie A this season, but has failed to play any part from the bench.
A graduate of Atalanta’s famed youth academy, Traore has made three senior appearances for the club and scored on his debut in a 7-1 victory over Udinese in October 2019.