Unai Emery remains desperate to boost his attacking options and Sancho has emerged as a target after Villa’s attempts to sign Marco Asensio ended in disappointment.
The latter is instead on course to join Fenerbahce after the Turkish club reached an agreement with Paris Saint-Germain.
An agreement to sign Sancho on a season-long loan is now thought to be in place, with the 25-year-old due to travel to Bodymoor Heath for a medical.
The move is separate to a deal which would see Villa goalkeeper Emi Martinez head in the opposite direction to Old Trafford.
Martinez is the subject of renewed interest from United, who are deciding whether to pursue a move for either the World Cup winner or Royal Antwerp keeper Senne Lammens.
The Argentina international was left out of Villa’s team for Sunday’s 3-0 defeat to Crystal Palace, with Emery claiming Martinez was not “100 per cent” focused.
Selling their No.1 would prompt Villa to move for another keeper, with Lammens and Porto’s Diogo Costa on their list of targets.
Former United defender Victor Lindelof is expected to join on a free transfer after completing a medical on Sunday night.
Sancho, who joined United four years ago from Borussia Dortmund for £73million, has spent the last 18 months on loan with Dortmund and Chelsea and is deemed surplus to requirements at Old Trafford.
The England international has one year remaining on his contract with United, who are likely to trigger a one-year extension option to avoid him leaving on a free next summer.