decoamorim Please make sure you're using the latest version of the spine-unity URP shaders UPM package, as this error was recently fixed in this commit.
You need to re-download the latest version of the package from the Unity Package Manager (via the Update button at the respective package), or even delete the Library directory in case the error persists after hitting the Update button at the package in the Unity Package Manager does not resolve the problem. If you see the line #define IS_URP_14_OR_NEWER 1 in com.esotericsoftware.spine.urp-shaders/Shaders/Include/Spine-Common-URP.hlsl on line 5, then you're on the proper version.
