ForceCrunchCompressionOff.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEditor;

namespace Paltee.Extensions
{
    public class ForceCrunchCompressionOff : AssetPostprocessor
    {
        void OnPreprocessTexture()
        {
            var importer = assetImporter as TextureImporter;
            if (importer == null) return;

            // prevent processing for existing assets
            if (!importer.importSettingsMissing) { return; }

            if (!importer.crunchedCompression) return;

            importer.crunchedCompression = false;
            context.LogImportWarning($"Forced off crunch compression for {assetPath}");
        }
    }
}