Juventus is not in good performance in Italian league, but in Europa league Juventus is focusing in Europa league, Juventus had serious challenge in their performance in Italian League in the early time of the season. Juventus are currently in their best form and this could be a hindrance for the Mendilibar squad if they don't implement a good strategy to be able to bring Juventus home. Juventus have two targets this season, namely winning the Europa league and securing a Champions League slot next season.
I think Sevilla are a good match for Juventus, If Manchester United had beaten Sevilla they wouldn't pose much of a threat to Juventus as much as Sevilla would and since they have a good record competing in this competition they will have some advantage, they have done it in the past we shall see if they can do again this time.