Most likely it will be like this, especially in this case it is clear the Bundesliga is easier for him because there the game is not as fast as in the EPL and indeed this will be good for him at the moment.
For productivity goals indeed in this case there needs to be a little more hard work but for adapting to the team I seem to have seen their cooperation well and Mane's adjustment was very fast.
Obviously it will be very easy for Mane because he usually plays quickly in the EPL and next season he will be in the Bundesliga with a slightly different game and not as fast in the EPL so Mane will easily adjust himself in the Bundesliga next season. And I believe that Mane will continue to do well in the Bundesliga and will also try to score more goals in the Bundesliga.
In terms of performance maybe but for this productivity Mane has to work a little more.
He has to be aware that when people's eyes see him it is certain that he will now continue to be portrayed as a replacement for Lewandowski so when expectations are slightly different it will make it difficult to say he is good.
He should really be able to create his own wave and try to beat the form Lewandowski had in the previous season so that he won't be labeled as a failed substitute.