But, if somehow Barcelona able to have them in their team at same time then we can expect amazing work and games against top team in La Liga and Champions League as well as hype is going nothing is clear because no one can predict where Messi is going to land for the next season and FFP problem allow Barcelona to have this player back into team.
I think also that Messi and Lewandowski will be a good combination even though Messi performance dropped comparing to its best days in Barcelona and Lewandowski is no longer young.
I expected much from Messi, Neymar and Mbappe, yet they weren't able to advance much in Champions League. We will see where Messi will end up and whether Barcelona will be sanctioned or not in the first place.
This can be a much stronger combination than what we saw in PSG because Lewandowski is a player who knows exactly how to finish the ball perfectly while the problem they had in Barcelona recently against Real Madrid match which made them lose the game was the problem they had in attacking midfield which can be solved after Messi joining this team and helping in midfield and attacking line with Lewandowski to make strong attacking power in Barcelona.