Mbappe is a newcomer so Ancelotti will not change the position of Vinicius Jr and Rodrygo who are old Real Madrid players as wingers while what Ancelotti needs is a center forward so whether he likes it or not Mbappe must be ready for that position because from the start the coach must have said it and Mbappe must be ready for all the consequences, but in my opinion it won't take long for Mbappe to adapt to the team he is basically a pretty great player in the striker position he just changes his position but has the same task.
Mbappe is new and if Ancelotti should risk the position of replacing Vinicius and Rodrigo position will only put the club at more risk because they were there before Mbappe and they were playing better before he later joined so he was just like a plus to the club, mbappe needs to be more than ready because everyone is looking to what will happen when he starts playing forward-center. he should know that his going there to play a serious game and not for the fanciness of playing for real Madrid, and with time am very sure that his going to take proper shape in Madrid changing leagues is what is currently affecting him but time will tell exactly if the changing in the league is what is affecting mbappe or is becoming lazy but I still have faith in the young man that he will do what is right when the time is right, just like the case of Benzema, mbappe will surprise a lot of people.
Changing league is not really what is affecting Mbappe performance but playing as a center forward is a challenge to him, because he is not used to that position. Last season Real Madrid was able to win Laliga and UCL without Mbappe and that is why Ancelotti is converting him to a finisher and not a winger because he is the new player to the club.
Vini is doing his job perfectly and Rodrigo making it impossible for Mbappe to play their wings. With time Mbappe will become what he was brought into the club for which is to support the club in scoring endless goals.
If Mbappe can now fully focus on his new role, he can gain great advantages for Real Madrid. It can be a good process for both Real Madrid and himself because his skills as a forward are very good. He also has finishing skills. Mbappe is a great player and I think he will get used to his position in time and continue to score goals.