public void OnPreprocessAsset()

This lets you control the import settings through code. Unlike other `OnPreprocess` callbacks such as OnPreprocessTexture or OnPreprocessModel, `OnPreprocessAsset` does not automatically register a dependency on the postprocessor. This means that if your subclass only implements `OnPreprocessAsset`, changing the value returned by AssetPostprocessor.GetVersion does not trigger a reimport of affected assets. To register dependencies explicitly, use AssetImportContext.DependsOnCustomDependency or AssetImportContext.DependsOnArtifact through the AssetPostprocessor.context property. Note: If your subclass also implements another callback such as OnPreprocessTexture, the dependency is registered by that callback and AssetPostprocessor.GetVersion works as expected.

using UnityEditor;class PresetEnforcer : AssetPostprocessor{    void OnPreprocessAsset()    {        if (assetImporter.importSettingsMissing)        {            ModelImporter modelImporter = assetImporter as ModelImporter;            if (modelImporter != null)            {                if (!assetPath.Contains("@"))                    modelImporter.importAnimation = false;                modelImporter.materialImportMode = ModelImporterMaterialImportMode.None;            }        }    }}