SheetsFabricMixin.java

import net.minecraft.client.renderer.Sheets;
import org.spongepowered.asm.mixin.Mixin;
import org.spongepowered.asm.mixin.injection.At;
import org.spongepowered.asm.mixin.injection.Inject;
import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;

@Mixin(Sheets.class)
abstract class SheetsFabricMixin {

    @Inject(method = "<clinit>", at = @At("HEAD"))
    private static void clinit(CallbackInfo callback) {
        com.mojang.logging.LogUtils.getLogger().error(
                "net.minecraft.client.renderer.Sheets loaded too early, modded registry-based materials may not work correctly",
                new IllegalStateException("net.minecraft.client.renderer.Sheets loaded too early")
        );
    }
}