What Barcelona needs now, is a good striker like Messi. If not, they'll keep finding it difficult to win matches easily.
This is what happens when a whole team focus their hopes and energy on a particular player.
It's gonna take Barcelona big time to form a formidable players force like Messi, Iniesta, and Xavi
You are right, right now barcelona must be able to find players who can really replace messi in their attack line, even though barcelona have depay and aguero but they don't seem to have fully integrated into the barcelona game and even they haven't been able to show their best game to help barcelona win, other than Fati who is rumored to be the next messi, he is has not been able to play consistently so far, the dullness of the Barcelona striker was seen against Dynamo Kyiv, even though Barcelona controlled the game and were able to create 11 kicks but only 3 were shot on target and even the winning goal for Barcelona was created by Pique who was a a defender.
A good striker to replace Messi is a must but their financial condition will not make it come true. There is no good players with cheap price and salary, so they should be realistic with condition. They should maximize what they have at the moment, or they will be in a worst financial condition if they force themselves to spend too much money to find player to replace Messi.