Like i rightly stated, I wont come to a conclusion on this matter. If he is a good coach, he will surely prove it in more than one season. Because some seasons are a fluke, being in the right spot at the right moment and luckily win a trophy. Manchester United almost did it last season but Tottenham took it away from them. Maresca should not be judge by one season performance, with time we will know if he is competent enough to lead the Chelsea team to more victories. But wining the Club World Cup and Conference league is quite a good performance for last season.
Well, I know it never right to judge a coach or even a player by just one season but I would say maresca will do well in Chelsea, coming in as a championship coach and being able to manage the youngest squad in Europe to secure a champions league football next season, winning the conference league and also finishing it with a club World Cup trophy shows he is technically good. It not just by winning these trophies but how he approach every game with different tactics and players shows he knows what he is doing and it not fluke.
He has worked under one of the best manager in the world, learned from him and showed that with Leicester by winning the championship. Chelsea bring him in and a lot of people criticize him and the new owners but right now I know a lot of Chelsea fan are convinced with him and his project.
Next season he won’t be under any pressure and Chelsea have also brought in a lot of quality and probably will still bring in more so personally I would say maresca will go well in Chelsea.