URP Custom (Unlit) Shader Graph Issue

I'm not sure if there's another specific post about this issue, and I'm not sure if it's a URP specific "problem" or it's because URP is meant to be like this.. anyways whats happening is:

I'm making a course about Visual Effects and I'm trying to make a custom Unlit Shader using Shader Graph to use in my particles. But in URP alpha is not affecting the shader. Both are set the same way (see attached images).

Unlit Master : Transparent, Additive.

I've tried to find something about, and I saw some posts but none of them worked to pass through it. Any possible solutions, or is it a URP specific stuff and I'm not aware?