Collision Shape Doubt

is there any way to change the character collision shape for a few seconds once the character pass by an action object???

 

Maybe not completely different shape, but you can try to change scale of character, and at the same time change visual by inverse scale. So it may scale just collision shape and leave visual as is (not tested).

 

i actually didnt understand where to do it, could you help me?

 

One solition is use 'Portal', where you can set new scale of character.