[Scripting Question] New Ability for Mega Kecleon

I'm working on an ability for my mega Kecleon on essentials v15.
with this new ability when kecleon attacks gets the same type of the move he uses(exactly like with protean). When he defends, BEFORE he gets hit by the enemy, he changes his type to be the same type of the move used on him(so for example if a pokemon uses surf on him,kecleon would change type BEFORE getting hit and would resist the attack) so this second part is really similar to color change, but im struggling to let the ability trigger before getting hit.

Can you make the ability work like Protean in both cases? What I mean is that at the moment you have some code to make the attacker change type if it has your new ability, why not in the same place make the opponent change type if it has that ability?