Bayern Munich should keep their attacking line as strong as possible as they have started to show a high level performance in the recent times. Mane needs to be treated as good as possible not to miss their PSG game at least. Besides Choupo-Moting might also leave the team as it seems. They need to keep their score contribution as big as possible.
For doing this we might see an offensive move in January by Bayern Munich maybe. I actually think that they were planning this for next summer but they might need this even in the middle of the season. The Bundesliga isn't much difficult for them maybe but they need to stay strong for the Champions League.
Bayern are becoming stronger with Mane in the team,their morals was somehow dwindled when Lewandowski left the team,but with time,they have been able to blend well again especially when they brought in Mane to come and fill the void left by Lewa,and with the games we've seen so far,even if he hasn't been able to score exactly the number of goals that Lewa scored,he has tried very well too scoring the numbers of goals he has scored.
And for the fact that they might want a January signings to boost their squad,especially in the attacking area,it will really be necessary now to keep them contenders of the tittle.
I think Lewandowski didn't leave much of an impact on Munchen after he left even Bayern Munich didn't experience a lot of downturn when Lewandowski go, because Mane could be the right replacement at this time, it's different with Liverpool which actually slumped when they released Mane to Munich,while Nunez who was expected to replace Mane was actually unable to do much, Munich has so far has lost many of its stars but I see that Munich can remain stable every season because the lack of competition in the Bundesliga, in my opinion, is the reason that Munich is still great even without star players especially Lewandowski.