In terms of the quality of the game, Leipzig is indeed better and it was very visible in the first leg match even though Leipzig was only 1 goal ahead. but that way there is still a high possibility for them to win again in the second leg when playing at home to Rangers.
while West Ham also played better in the first leg but they lost to make it a little difficult for them in the second leg later when playing at home to Frankfurt, although anything is still possible and this match will be quite interesting because the game between the two teams is very balanced.
In my opinion, Leipzig and West Ham will reach the final of the Europa League this season even though Frankfurt are currently leading 2-1 over West Ham in the first leg. Leipzig are a good team and they were convincing enough to reach the final.
Here I am not underestimating Frankfurt who managed to beat Barcelona in the second leg surprisingly recently, but I think they will struggle to reach the final even with a one goal advantage in the second leg. West Ham only need to try to score at least 1 goal in regular time (90 minutes) to go into extra time and that will open up more chances to win the game. But it would be interesting if Frankfurt scored the first goal at home.