I know this question is a little bit old, but i stumbled ober it with the same question in mind.
I think their is another way to do so, therfore actions can be triggerd without neccesarly entering the collider first. So if spawning in an collider it also can be triggerd.
Getting the Actors ovelapped of an Collider, can be used to exectue method on them, what is kind of unity on trigger stay. How to execute actions without an neverending update or here event tick is the question what have to be solved in the special usecase.
Hope it helps other developers 
Greetings