Render transparent mesh over sprite

Hey there community.

So my question is pretty straight forward. I would like to have a unlit, single-color, transparent, 2D mesh rendered over a sprite.

I can render my mesh over the sprite by using something like Unlit/Color but that doesn't allow me to use transparency.

I did write a cutom shader thats basically the same as Unlit/Color but does use transparency, however if I use this shader the sprites behind the mesh completely dissappear...

I just don't understand shaders... Could you help me out on this one?

Cheers