You can change the hair style with weapons in Unity.
By using the attached image and skin it will be.
Be replace the images contained in this items (bones) below.
- Weapon: res_weapon
- hair: export_Spine/cutegirl_SkeletonData in unity
If you want to use this asset, you should download the appropriate Spine runtimes.
The runtimes can be downloaded from EsotericSoftware's Github.