The Mexico striker, who is said to be unsettled at Old Trafford, is attracting interest from across Europe and the Premier League champions are prepared to let him go
Goal has learned that the Primera Division duo have identified the Mexican, who has struggled for first-team opportunities under David Moyes this season, as an attainable summer target.
Atletico could lose Diego Costa this summer, with Chelsea boss Jose Mourinho particularly keen to bring the Brazil-born Spain international to the Premier League.
Hernandez had previously been open to the idea of a move to Russian club Rubin Kazan, but United quickly ruled out a move for fear of being short up front for the end-of-season run-in.
Valencia is expected to complete the sale of the club to a new owner in the coming weeks, whereupon it will move forward with its transfer plans.
Singaporean billionaire Peter Lim first expressed an interest in buying the Spanish club in December, and although he was targeting a quick deal, he is yet to reach an agreement.
Despite being considered the leading candidate to purchase the club as recently as February, however, Lim is no longer seen as the forerunner.
Jorge Mendes, the agent who has helped broker a number of transfers at Old Trafford over the years, including those involving Cristiano Ronaldo and Bebe, will oversee Hernandez's sale.
Mendes also represents top-level names such as Radamel Falcao and Jose Mourinho and would prefer to do business with Lim should he assume control of Valencia.
Serie A club Inter has also been linked with a move for the striker, who joined the Red Devils in 2010, as new owner Erick Thohir continues his San Siro overhaul.
Hernandez has reportedly become disillusioned with life at Old Trafford under Moyes, who was chosen as Sir Alex Ferguson's replacement at the end of the last campaign.
The Mexico international has started just 10 matches this season, including three in the Capital One Cup and one in the FA Cup.