Changing value without Actor's input

Hello. Is it possible to change values of actors with other character without input with them? Just take a value of an actor and change without cast or Get Actor
Screenshot (345)

a value of an actor

You said it yourself - you need a reference of the other actor. You have 10000 actors in the scene. How is the editor supposed to know which one you mean.

Or a better question: how do you know. Perhaps there is an easy way to reference it - but to point you in the right direction, we’d need to know more about those actors.

What they are, what is their relationship and purpose & where they are.