Question Use renderer textures with a transparent font instead of the skybox

Hello, I am a Unity developer for a video animation studio and I want to use the renderer textures in Unity HDRP 2019.4.9f.

The goal is not to use After effect anymore for the composition after each render.
(What i want : ⚠ FAKE SCREEN ⚠)


But I have a big problem, I can't use renderer textures with a transparent background.
I have one camera and one canvas for each plans i want to show :
(The setup of my scene : )




The result is here on the gameview. From what you can see, the skybox hides the other plans.

So i tried to set the camera with background --> none
(But that doing weirds things


I also tried with a green background to remove it by adding a shader, but the bloom effects or other do not work with it.
(exemple : with just a cube has the renderer texture)


I have no more idea, is there a solution or another possible method?

Thanks for reading!