The Argentina international, who played in the 2014 World Cup final, is likely to start against Wolves on Saturday.
The West Midlanders are enjoying a superb return to life in the Premier League following promotion from the Championship last season and are currently sitting seventh in the standings.
Prior to the 2018-19 campaign, Wolves won the Championship title in style, finishing on 99 points with 82 goals scored and a goal difference of +43, and manager Nuno Espirito Santo has stuck to his guns in terms of his philosophy.
Such big results picked up by Wolves this season include wins over Chelsea and Tottenham Hotspur, along with draws against Manchester City, Arsenal and Manchester United, plus the third-round triumph over Liverpool.
Romero has played every FA Cup game for United this season and is likely to also feature against Wolves, while at international level he has 96 caps for Argentina and played in two World Cups including the 2014 final (Transfermarkt).
He told the official Red Devils website: "We’re really excited about the game ahead of us, it’s a really important game against a team that have done really well this season.
"They’re a top side with some really good players and their style of play means they have adapted really well to the Premier League; their style suits this league. So it’s a big challenge but we’re prepared and confident."
Wolves' last FA Cup success came in 1960, though they did also win League Cups in 1974 and 1980, while Man United last won the FA Cup in 2016 and the League Cup a year later along with the Europa League.