Bringing in players who are already registered in the Champions League with other clubs cannot help Chelsea, they can only play in the domestic league, while the Champions League must wait for next season. Ronaldo is very likely to be played in the Champions League because the club that Ronaldo defended before did not qualify for the Champions League. This situation can be used by Chelsea to increase their strength to compete in the Champions League. Ronaldo really can't do much and isn't as sharp as he used to be, but his experience and skills can help Chelsea go a step further.
yes it is very profitable for Chelsea to improve their quality in the champions league arena. this possibility will come true if ronaldo agrees to the proposal from chelsea. Chelsea need someone who is more experienced in the champions league to realize their hopes of becoming ucl champions this season. Chelsea will face representatives from Germany for the round of 16 where dortmund will be their opponents. If Chelsea don't improve in the winter window, maybe Chelsea will have a little trouble when they face Dortmund. Dortmund is a team that hinders big team teams in the champions league especially this season dortmund has players on the rise like Bellingham of course that will make it difficult for Chelsea to win 3 points.