Indeed, Chelsea performed well in the UCL. They have a chance to win like Tuchel. But with the current conditions I doubt it. I don't think current players can compete with Man City, Munich or other big clubs. In 1/16 they will play Dortmund. I don't underestimate Chelsea, but Dortmund can always surprise. Chelsea must be vigilant. Even though that game is still a long way off, there is a chance Chelsea make a big transfer maybe that could change the chances of getting to the Final.
I don't think that any transfer can seriously change the chances of the teams (unless of course it's Haaland + Mbappe, but they hardly want Chelsea plus they can no longer play for another club in the Champions League this season). Maybe we will see Ronaldo's move that has been talked about so much? He's not showing anything special this season, but he has a certain Champions League magic associated with him.
Currently Halland Perfect for Manchester City and Manchester City Perfect for Halland. At the moment, if Halland goes to another club, I think he will not have the same opportunities as Manchester City, because the players that Manchester City currently have, except for him, are playing football in a great understanding with Holland. On the other hand, should Kylian Mbappe really leave PSC, if he joins the Real Madrid team, it will be a big gain for him.