imo , chelsea hasn't reached its peak performance yet. I believe Pochettino is still figuring out the best combination for the team, and it might require a few more players to establish a strong second layer team with solid performance.
There are some new players who are still injured so he hasn't done the first game yet. If it's not fault he is Christopher Nkunku's, he injured his knee and had to have surgery. But it seems Christopher Nkunku will be ready for the International break match. If he does come back then it could be Pochettino's option in attack. Even if you look at Chelsea, they still need a lot of quality players according to Pochettino's character. They can still take advantage of the transfer break this season.