The performance of Bayer Leverkusen csn not be compared to that of their opponent when compared to the current form of the teams, you already pointed out the difference between the teams and how new they are in the champions league games which I think is one or the advantage of Bayer Leverkusen playing against them not juat that but the performance of the teams in their domestic league shows that they have little or no chance against Leverkusen. I think Leverkusen doesn't need a miracle this time they just need to stay focus be concentrate on getting better because they have a better chance of going far in the champions league this season.
In the next match for Bayer Leverkusen which they will be a guest at Brest's headquarters is something that will not be difficult for Bayer Leverkusen if the Leverkusen players still have a good enough tactic to win at their opponent's home and beat Brest as the host. I wouldn't think it would be easy, but I have no doubts about the quality of Bayer Leverkusen's players in the next match in the Champions League, because Brest's strength is certainly not quite on par with Leverkusen at the moment even though Brest will also play all out to be able to win at home.
You are right. Bayer Leverkusen are stronger than Brest obviously, even though Brest will be playing at home, and they will want to do everything possible to win against Bayer Leverkusen, but it will be something difficult for them to win against Bayer Leverkusen. Brest are not in good time either, so even if they will be playing at home, Bayer Leverkusen are going to be ahead of them regardless. As long as Bayer Leverkusen will perform the same way they are doing in the Bundesliga, I don’t think they will find it difficult to beat Brest.
Besides that the quality of League 1 and Bundesliga is different and as far as I know Bundesliga is superior to League 1 so I think Leverkusen is more favored to beat Brest but still we don't know what will happen in that match because Brest also can't be underestimated in the Champions League they performed well but in the domestic league they are not so good I am also surprised and I think Brest is more focused on the match in the Champions League so Leverkusen needs to be careful when facing this club they could give a strong fight especially since they are playing as the home team.