None of them are KKG level. KKG aimed at the ground would destroy Onigashima.
Wano and Dressrosa are countries, not small islands. Onigashima is like Green Bit, probably even smaller.
DR is a big island,not a entire Country like wano who has multiple city mountains, villages and overall a large land.
Not saying DR is small,but wano is at least the 3-4 size of DR if not larger.
And nope Law new attack basically above KKG who just split a town in multiple parts. Current KKG should do a better feat though,but KKG is not Luffy Finisher against Kaido, we will see something new.