The 19-year-old is yet to make his first-team debut for the Red Devils since arriving from Penarol in October but has been involved on eight occasions for the club's Under-23s and Under-21s, scoring three times.
A recent report claimed that United were open to the idea of the summer arrival leaving on loan in order to continue his development away from the club.
Lasalvia, who represents Pellistri, has told Fichajes that the teenager is expected to spend the second half of the 2020-21 campaign in Spain.
The agent did not mention which club are at the head of the queue, but English journalist Jonathan Shrager posted on his official Twitter account on Friday afternoon that Celta Vigo were the favourites.
Pellistri, who has been training with United's first team this season, scored twice and registered four assists in 37 appearances for Penarol before moving to Ole Gunnar Solskjaer's side.