Hello Anapsys,
You could create an image variable and use a “Make Slate Brush” Node in your binding and then make the image variable public. This will allow you to change that image variable from anywhere. This will in turn swap out the current image that is applied. I have made a simple example below. I hope that this helps.
Example (This example was done in 4.8):
Here you can see that I used a “Make Slate Brush” node. to do this you will drag off of the dark blue return pin and type “Make Slate Brush”. From there I simply dragged off the image pin and promoted to variable.
In this example I am swapping out the images with a button click and a flipflop node. This will toggle between the two images every time the button is clicked.
Make it a great day