I didn't think about URL restrictions for the web exports, that is interesting. I'll have to look into it =).
For 1st/3rd person view I only use one camera. It is for the inclined movement that I need two of them.
The body doesn't move in the direction of the camera but on the direction of the input. The camera rotates the body based on the direction it is looking at. When I tilt/incline the body based on the slope inclination I now have to be careful how I rotate the body.
So I guess one way to do it, is to incline the base, and then let camera rotate only the visuals. But the direction has to be rectified so that it follows the direction the visuals are facing. It seems to be easier to calculate that direction when the camera has the same inclination as the body.
So I keep one camera on the body and one external camera that is not affected by the inclination.
I guess you don't really need 2 cameras for this, on the body you could use a node3d/marker3d and feed it the camera rotations, but it was easier for me to just duplicate them and I get the benefit of switching between them if I want to see the view from the inclined camera or the external camera.
Unfortunately, this kind of works and kind of does not. In my tests I found so many bugs that it was easier to start from scracth.
In the test movement it is only the camera that inclines with the body as I was still working on the other one when I uploaded the project.
I fully agree with the sliding being terrible. I am testing both CharacterBody3D and RigidBody3D. CharacterBody3D doesn't really have the sliding issue, but forcing it to walk on a 360 slope remains a challenge. The RigidBody3D has no problems with the 360 slopes but it has the sliding issue.
It seems I can't fix neither =).
Thank you!