I have managed to get a custom additive version of "Unlit - Transparent Colored" to clip my sprites properly within a panel using the normal "Soft Clip" method. My issue is that there are some cases in our project where I need to use Texture Masks for clipping, and sadly the sprites using "Unlit - Transparent Colored Additive" do not clip properly, nor do they seem to use "Blend SrcAlpha One", for the additive blending.
The only modifications that I have made to the 3 custom shaders is changing the name and the two lines with: "Blend SrcAlpha OneMinusSrcAlpha" to "Blend SrcAlpha One" for the additive effect as an overlay on my sprites. I found the method on this forum.
I am curious if anyone has run into this issue as well? It is sort of an edge-case.