Enzo Maresca needs to learn from the pre-season game they played, plus the challenges he will face next season with the players the team provided to him. Chelsea is not a team that is patient with its managers, they are always interested in achieving good outcomes each season. I won't think about Maresca as a bad manager only because they failed the pre-season games, I believe Chelsea will recover and win their games.
Enzo Maresca seems like a manager that will take time to adjust to life at the big boys table, he has been staff for a while, but manager for less and I think it is going to be not that easy to get good results right away. Just because he studied and worked under Pep Guardiola, doesn't mean that he is going to be great and I believe that he is going to face some issues about managing player as well.
What Pep does is not simple, I know that Pep always worked with amazing teams and that's why everyone keep saying that what he did is a hard thing that not everyone can do, but the reality is that I have seen squads better than current City and yet they ended up being not as good as City, that's the simple reality. Look at how much money they spent in the last 5-10 years, there are teams that spent more and got nothing in return.
So Chelsea should be fine, they spend a lot, but I am not expecting top three from them, even four would be very hard, best case for them this season is top 6 at the moment and they will probably do that unless they suck. This is why Enzo has a very tough job, he is taking over a team that is barely there, and it is going to be very tough for him to build this team.