I have my doubts about Barcelona, of course because they are very unstable in many games. I don't think their win vs Atletico Madrid is the start of their comeback this season to continue competing until the end of the season, but it's good if they can maintain their form.
Espanyol is not an easy opponent for Barcelona and I think it will be a difficult game to predict. If Barcelona win then they can get back to 4th place again today by shifting Atletico Madrid to 5th place. But there are doubts about their chances of winning, I think today's result will be a draw.
Though the form of Barcelona is not good enough but the history against Espanyol is good. Espanyol won against Barcelona in 2018 and after that Barcelona is doing really great and unbeatable against Espanyol after 2018. I'll still put ahead Barcelona as favorite.
Don't know if there will be an audience. Espanyol needs that. Barcelona may not be the star team they used to be, but they should be able to beat Espanyol. You can't call it a real away game. Barcelona is having a hard time this season, even with lesser teams. Xavi has now started an upward trend. Barcelona must continue that line and then try to lose as few points as possible to be able to play a significant role in the competition at the top.