On paper, Juventus are the main favorites in this match and that is clear after Sevilla can't perform well in La Liga, but what will be difficult to predict in this match is when Sevilla can perform well in the Europa League. A tough task is definitely in front of Juventus, don't let them underestimate the club that will be their opponent in this semifinal, because if they underestimate it too much then they will be defeated by the Spanish club. But I believe, Juventus is not a club that will underestimate its opponents, they are a big club that is more experienced at the European level.
Of course, Juventus is the favorite team to qualify for the final round. Juventus has a stronger squad and they are a more established team. While Sevilla still can't perform well constantly, especially in La Liga. But they can surprise us when they eliminated Man United in the previous round of the Europa League. However, everyone must be aware that Man United was defeated because they made their own big mistakes. Man United defenders performed very badly, they even made 2 scores for their opponent (Sevilla). 
While Juventus looks like a more solid team, their defenders seem much better than Man United. So, I think it is a very different situation now, Sevilla won't get goals easily anymore. So, ideally, Juventus will qualify for the next round if they can play as expected.