This is Barcelona's home match. And considering only the home match I consider Barcelona as favourites. In fact I find my Barcelona and Manchester United squads equally strong. However, Barcelona is stronger in home matches. Barcelona are hard to beat at the Camp Nou. However, the recent performances of both the teams are quite good. The players of both the teams are confident now. We should be ready to see any results.
Hard to beat at home doesn't mean Barcelona can't be beaten by their opponents on their own turf. Even if you think about the chances of victory, indeed Barcelona has a slightly better advantage because the match with Manchester United will take place at home to Barcelona. But Manchester United themselves are also very aware of this so they will also play their best at home to Barcelona in order to be able to balance the game they will face later.
Barcelona are now in one of their best performances. Since Barcelona's match against Manchester United is at Camp Nou, Barcelona has a high chance of winning this match.