Yes, it was not easy for Real Madrid to qualify for the final because ya, in reality Atletico also managed to play well in the match. So indeed, it will be a definite result for Barcelona to win because of course, Barcelona will also do well to still be able to play in the final against Real Madrid later. Because ya, about the Champion League and La Liga it seems difficult for Barcelona to get a trophy this season and therefore, the Super Cup and also the Copa del Rey are one of the chances for Barcelona to be able to get a trophy this season. So yes, I personally believe Barcelona will win in normal 90 minutes against Osasuna in this match.
Real Madrid played against Atletico Madrid in the Semi-final of Spanish Supercup. Atletico Madrid is one of the top team in Spain, it must be different with Osasuna. Barcelona is lucky to play against Osasuna, I am not sure they will qualify for the final round if they played against Atletico Madrid in the semi-final. However, it is good that Barcleona could win the match today and Lewandowski contributed to score a goal again. Thsi will improve the motivaion of Lewandowski and Barcelona as a whole.
For the final round, it will be very interesting because we will have an el classico match (Real Madrid vs Barcelona). It will be difficult to determine which team to win the trophy of Spanish supercup. However, if we consider the current performance of those teams, Real Madrid looks as the favorite to win the trophy of Spanish supercup this season.