I don't think Chelsea has any problems with the players they currently have, I mean they can hire better superstar players and there are some players linked to this team like Barella, Páez, and Matos but I don't think even if all these three players will help this team because Chslea needs better coach than Lampard and then they new coach should start seeking for better players.
Yes, that's why I said that Chelsea don't really need players at this time. What Chelsea needs more is a coach who can use Chelsea players to bring Chelsea to become a strong team like a few years ago.
In these 2 seasons Chelsea has had problems in having a coach so management must prioritize finding a better coach instead of recruiting new players.
I agree with you that when Chelsea will have a better coach then they can recruit some star players to strengthen their team.