Version: 2021.3
public ModelImporterClipAnimation[] clipAnimations ;


Animation clips to split animation into. See Also: ModelImporterClipAnimation.

When you import a file for the first time clipAnimations will be always empty. If you need to populate clipAnimations before the first import you can use an AssetPostprocessor and override AssetPostprocessor.OnPreprocessAnimation.

using UnityEditor;
using UnityEngine;

public class CreateAnimationClip : AssetPostprocessor { void OnPreprocessAnimation() { var modelImporter = assetImporter as ModelImporter; modelImporter.clipAnimations = modelImporter.defaultClipAnimations; } }