Unfortunately we don't get to see Sadio Mane and Lewandowski play together at Bayern Munich. According to a report by Marca (reputed Spanish media), Lewandowski reiterated his desire to leave Bayern Munich and will join Barcelona for next season.
The unique thing about Lewandowski's desire to leave is that he wants to be useful even in the remaining 1 year of his contract at Bayern Munich, he said that if he sold himself to Barcelona, it would be very good because Bayern Munich would benefit financially.
Lewandowski's desire is different thing but his contract says he has one year left at Bayern and Bayern wants Lewandowski to continue and fulfill the remainder of the contract. It could go either way and it all depends on Bayern but right now Bayern wants Lewandowski to play until his contract runs out as it seems. So yeah, we might be able to see Mane and Lewandowski linkup but I am sure we won't be watching Lewandowski with good morale at Bayern.