Maybe Chelsea studied how Botafogo was able to win against PSG. The Brazilian team was able to withstand the attacking powerhouse of Luis Enrique's side and defended the one goal they scored in the 26th minute. Enzo Maresca was able to assemble a team that had a strong defensive and attacking mentality. For now, Chelsea is one of the best clubs in Europe, and their performance next season will determine how well they have improved.
Personally I don't agree to that Chelsea studied any team for them to get such great result, I think Chelsea played their football they way know it, the had a game plan which they were able to implement on the field that day, they played without fear, they forced attack very early and to their greatest surprise their plan worked they continued with that pattern and before we could know it were now counting 3:0 already in the first half, Chelsea will always be Chelsea in the finals, I know that i have said this countless times, any football enthusiasts that has been watching Chelsea play will attest to this, although many players has left but the blues high spirit in the finals remains intact, yea Enzo moresca did a great job and I give him kudos for that.
I didn't see any other team in Chelsea in the final. You are right that Chelsea were Chelsea in the final. They beat PSG 3-0 with their own plan and attacked PSG's confidence very sharply with their attacking spirit, from which PSG completely collapsed. Part of Chelsea's plan was to attack as much as possible in the first half and score as many goals as possible. They were successful in the first half. Maybe their plan for the second half was to play defensively and counter-attack strongly. They were almost successful there too, but they could not be completely successful because of two great saves by the PSG goalkeeper. I will not forget to give credit to Chelsea's goalkeeper in particular, because he played a big role in this victory.