Unity 2020 URP fog of war

Hello guys, i'm new to unity and I have a question about shaders / cameras, I'm trying to create a "fog of war" feature for a little game. For the moment I tried this:

• 1) Create a camera that will display only the terrain and characters and render to texture: https://imgur.com/1NLcvk6

• 2) Create a camera that will display only the "FOV" mask and render to texture: https://imgur.com/vOIRbuy
  

• 3) Create a shader graph that will multiply texture 1 by texture 2: https://imgur.com/fSGiSAP

Problem is I don't know what to do next to apply the result of the shader to final scene. I tried to use "Renderer features" of my Forward renderer and apply a material containing this shader, but it's not working because all my cameras are affected by this renderer. Unity don't let me to switch camera renderer to another one.