It depends on how they perform, if they are in a relatively easy group but they fail to perform well, I think that will also be a problem. We can see how Manchester United fared in the Champions League group stages this season. They were the favorite team to qualify for the group, but their performance was very disappointing and that meant they had to fail and they were even ranked last in the final standings.
Leverkusen is a team that is playing well this season, even though they are in a difficult group, but if they can perform well I still believe that they will be able to qualify from the group. Once again this depends on how they will look. Whether they will play well or not. This requires consistency, that is one of the important factors that every team must have. Xabi Alonso must have realized that their opponents were a good team too, so he had to prepare everything very well.
Well I don't why my thoughts are this way but I feel Bayern Leverkusen this season will be the center of eyes of all their opponent they are playing because in the football world now knows the capability of this team and will definitely not underated them and this was what Leverkusen also used to win lots of games as team didn't actually knew their capability and aslo game style but this time this case would be different and that's why they need to work hard @xabi Alonso.
It's not just you who think like this, but almost everyone will also think like that, because what they did this season was truly extraordinary and it attracted a lot of attention to them. Now many people are waiting and want to see how Leverkusen will perform in the Champions League next season, whether they will perform well or vice versa. This is something we usually see if there is a team that usually performs normally but this season performs extraordinary, that will make them get a lot of attention.
Not only them actually, Girona will also receive greater attention than usual after they managed to get to 3rd place in the La Liga standings, which is very difficult to get there. However, there will be differences from Leverkusen and Girona, because Leverkusen finished the season without defeat in the Bundesliga and they only had 1 defeat in all the matches they played this season. So attention to them will be much greater.