For years I used Unity and did cool things, but since they started with RP URP and so on, I can’t find the solution to do cool things because nothing works. If a shader works on sand, the one on rocks doesn’t even work in the sea. If you switch to another editor without URP, sand works, but sea and rocks don’t. So there is no way for everything to work in all editors with and without URP. But everything uses the same textures.
at least theres error messages in console and shader has some warning about linear texture too…
could try fixing those errors/warnings, to see if that helps?
You’re probably mixing assets that were made for URP and assets that were madefor the built-in renderer. These are two separate, incompatible renderers. The texture doesn’t matter, it’s the shader that makes one incompatible with another.
If you have assets for built-in you might be able to convert them automatically.
https://docs.unity3d.com/Packages/com.unity.render-pipelines.universal@7.1/manual/upgrading-your-shaders.html
If I put a fish and a camel in the desert, the fish dies. But if I put them underwater, then the camel dies. Damn! can’t have the camel and the fish coexist in peace! 
Jokes aside, you can’t use shaders for URP in the built-in pipeline, or vice versa. In general you can’t mix and match shaders between multiple pipelines, because shaders are designed with a specific pipeline in mind. You’re supposed to stick to one pipeline, then use shaders designed specifically for that pipeline.
As kdgalla said, textures don’t matter: they’re just images. It’s the shaders you use which determine whether a material will show up properly in any given pipeline, as these interact with the lighting system - which is completely different in each pipeline.
In 2019 i would have said: read the documentation because it was good and it was all there…
Now is more accurate to say: for your own good, try another game engine.
But anyways if you really need unity for this. Check the errors and try with another material, i’m pretty sure you are using an asset from the asset store, if that is the case, then, is not unity’s fault. It would be more like:
1 - You don’t know what you are doing (which i really doubt)
2 - The asset you bought is not compatible with this version of unity (most likely the main reason)