The advantage that Sporting gets in the second leg is that they will play as the host. And interestingly in the previous round, when they got rid of Arsenal in the second leg, they were playing as a visiting team. It's little things like this that Juventus have to pay attention to. Now they have the advantage as they only need to draw to make sure they are in the next round. But on the other hand, what they have to watch out for is that Sporting will play all out in this match. Because the victory by creating 2 goals is what will make them in the next round.
Sporting's defeat in the first leg doesn't seem like the end of their struggles this season in the Europa League. Sporting did well in the first leg, it's just that they were very unlucky with some of their attempts to score. Sporting dominated possession in the first leg despite playing at Allianz, they also had more goal attempts, but they were very unlucky.
So of course Sporting is unlikely to give up on Juventus in the second leg. They are playing at home, it is a good advantage to expect a great performance. Regarding the possibility of victory, it is still possible but it depends on how Juventus handle the resistance of Rúben Amorim's team.