~Snip~
They will face Real Sociedad in Spain and the first match will be difficult away. Also, Real Sociedad, who they will face, is one of the strong teams in Spain. They are strong enough to beat Manchester United, who are not in form. Therefore, if they want to advance to the next round, Manchester United should not lose in Spain. They can win the match in England, but their job is really difficult in Spain.
Real Sociedad have always been a team that often causes problems for the big teams in La Liga, the last defeat to Barcelona was because they played with 10 men from the 17th minute, overall their performance was not as disappointing as Man United. In my opinion, the only big problem that Man United have is playing at Sociedad's home ground, it is very difficult to beat Sociedad when playing at their home ground, so the final result is clear who will win and who will lose.
It will be a difficult match for United whose performance is not improving. Hopefully, they'll be able to overcome the challenge and advance to the next round. It's Europa League, and no club is favorite until we see their performance on the field. Real Sociedad might be tough in Laliga, but United will make things difficult for them.