I agree with you. Copenhagen has already proved their mettle. And after watching Copenhagen's performance against Bayern Munich, I feel there is no way to underestimate this team. This team has the ability to be confident and perform well against bigger teams.
Manchester City's performance is still a bit shaky. Due to their weak midfield, the team is not getting the expected performance from Haaland in attack. So the Copenhagen vs Manchester City match is likely to be competitive. However, if Haaland and De Bruyne play well, it will be a little easier for Manchester City to dominate the match.
Despite Manchester City's dismal performance, I don't believe Copenhagen will have a chance to triumph over them. Because they want to return with their best effort and win the game, Manchester City is now ready for the encounter. They will provide a remedy to Copenhagen Man City only have problem with midfield. Other than that, I have no doubts about their ability to perform effectively throughout the game.