How do I trigger a next-to-edge animation?

So I want to make an animation to use whenever you're near the edge of a platform, floor, or whatever solid you're sitting on top, kinda like you're lossing your stability.

The problem is not creating the animation, is the triggers.

Do I have to set the player animation to every posible object the player could be on top or is there an easiest way?

Thank you

Have an invisible sprite near the edge of the map, when mouse is over, scroll left (or whatever direction).