Adaptation is necessary, but from some players who are really great and have the capability, it doesn't take them long to adapt and show their good performance. For example, Erling Haaland at Manchester City and Jude Bellingham at Real Madrid. September 4th we'll see Lyon match against PSG, Lyon is a pretty tough opponent even though they're currently at a slump at the start of the season, we'll see how PSG can see a good opportunity here or not.
Kane also started to play well in Bayern. This may be the case and some players are easier to adapt, but we gave examples of players who definitely had a place in the first team so they did not have much anxiety that they would have to compete for this place. Although everything was a little different with Messi, he had a permanent place in the team, but for a very long time he could not show the game that was expected of him.