i can't find a way to consistently choose (transparent) 3D models' sorting

ok so basically, while making a 3D game in godot, i've come across this problem multiple time and i can't find a solution anywhere

first i had this problem where, with two 3D sprites (with transparency and y-billboarding enabled) in the same exact position, so i couldn't really choose which one was above the other. I simply fixed this by trying over and over to find a solution until the sprites were randomly in the right order.

but then i had a similar problem when making a cloud skybox. I made it with a mesh with flip faces enabled, and a noise texture to make the clouds, with transparency enabled as well. The problem is, the skybox should always appear behind everything else, and i tried everything, sorting offset, disabling depth test, using the render priority, etc.

I know this has probably something to do with transparency, because godot itself warns that transparent objects are always rendered above opaque ones. But i dont know how to fix this, so does anyone know how to? Also sorry if i probably missed some details, if there's anything else that could be causing this i will provide explainations.