Shader sprite overlay other sprites

I am trying to create a sprite overlay/shader. That I can apply to a sprite that will apply to the sprites under it. In the image I so a base sprite that will not have a shader then a sprite that will have the shader. What I am trying to to get the effect of is when the shader sprite is over the base sprite it will invert the colors of the overlapping pixels. As the image I made it shows that where is overlaps the color changes but not on the sides of the base sprite. The effects would ideal would work over multiple sprites. I have created a color invert shader but the overlay effect is what I am going for.

The image above so the effect I am trying to acheive.