With a tic tac scheme? I don't think so, that must long time adaptation, this is a big difference between Barcelona and Munchen using the long passing ball to Lewa. maybe a little stiff when first time playing with the strategy where he must run and move quickly to outwit the opponent. Exception if he only stands in front without picking up the ball.
Perhaps Robert is not a player who adapts very quickly. But I'm sure it won't take him very long, the first two games, or even one will be uncomfortable for him, but I think before the season in training he can already feel at ease, so I'm not worried about his game. He is a very talented player despite his age, it will be a very good acquisition for Barcelona
Lewandowski is used to Barcelona style of play, because he had previously been coached by Pep Guardiola when both were at Bayern Munich. Adapting to the style used by Xavi is not something difficult for Lewandowski, while at Bayern Munich he has been coached by different coaches, he is able to play well and his goal productivity is also very satisfying. The reason Bayern Munich set a high price is because Lewandowski is still able to play at a high level even though he is 33 years old, Barcelona can use his services for another 2 or 3 years if they manage to bring Lewandowski to Camp Nou.