The 22-year-old spent the first half of the season on loan in his native Portugal at Vitoria Setubal, where he made 16 appearances in all competitions before United activated the recall clause in the agreement earlier this month.
His switch to Belgium is Pereira’s fourth temporary spell away from the Reds in total, after also spending time out on loan at Rochdale in League One and Portuguese side Belenenses.
Our no.40, who joined United in 2012 after a successful trial period with the club’s Academy, made his first-team debut as a substitute in a 4-0 FA Cup win over Wigan Athletic in January 2017.