I don't know about Bologna, but as for Girona I'm sure they will perform well, at the beginning of last season they were performing very well in their domestic league and even towards the middle of the season, at some point they were even at the top of the table in the Spanish la Liga for a while before Madrid took over the mantle. so I think they have the temperament and the composure to chat a new course in this their champions League journey. If Girona continue the way they played last season, then they are a team to watch out for.
Bologna lost two of their best members, the head coach who moved to Juventus, and the central defender Calafiori who moved to Arsenal. Even these people stay with Bologna, a new season will be very challenging for Bologna. In reality with these human resource losses, Bologna will have a more considerable challenging season.
Girona don't have big loss in human resource like Bologna but the transfer season is on and they are facing with pressure from big clubs which want to bring star players from Girona to their clubs. Bologna and Girona both will be challenged by unfamiliar schedules and playing intensity in both domestic leagues and Champions League.
I am more confident in Leverkusen ability than Girona, since under the guidance of Xabi Alonso, Leverkusen has turned into a club to be wary of. Girona ability is not yet able to match Leverkusen strength, if these two teams meet, it is clear that Leverkusen will win the match. Although surprises can happen in football, I am not sure Girona can do it because they will have a hard time competing with other strong teams.
Leverkusen have better foundation to play well in a new season than Bologna and Girona. Their player quality and resource is better and Xabi Alonso stays with them as a head coach. It is a big support for their stability in tactics and training which can be basement for their success in a new season. Xabi Alonso decided to stay with Leverkusen and he aims at another successful season with Leverkusen before finding opportunity of moving to Real Madrid.