This is a paid asset, but now you can download Spine2Unity Native Animation Free.
Detail this asset from Unity Store: Original Link
Spine2Unity Native Animation v4.0 (Latest version)
Require Unity 4.5+ or Unity 5.0+, Unity 2017, Unity 2018, Unity 2019, Unity 2020 (All version Free/Plus/Pro)
Best Spine convert tool for highest runtime performance and continue auto optimize (base on Unity Native Animation system). Full source code inside for easy custom or create automation export tools
Feature:
– Can work for all Spine version 1,2 & 3.
– Support export to Sprite Renderer.
– Support export to UGUI Animation.
– Support export to NGUI Animation
– Version 4.1: fix bug export on Unity 2018 & 2019
– Calculate and record from export process, NOT require update or recalculate in runtime for highest CPU performance.
– None Script or library requirement in editor or runtime.
– Full create Skeleton, mechanism and Unity native Animation, easy to reusable Skeleton and animation with many characters you have.
– Prefer render by Sprite Renderer, Mesh and Skinned Mesh are also supported. – Image render in scene is most beautiful with pixel perfect and NOT blur texture.
– Auto create Atlas Sprite, easy to scale atlas image with any size you want.
– Easy to change Sprite in any bone of skeleton, it’s also support for dynamic loading from AssetBundle or images for network.
– Very Easy to add plugin object(with itself skeleton,animation, or particle effect) for any bone of objects.
Limitation:
– Not support IK mode yet.
– Animation by skinmesh is not exactly in some case.
If you using with by skinmesh please use by Spine support for better animation, If you want to reusable skeleton, animation, saving resource, full editable and easy customize character, easy to dynamic loading, this Tool is the best choose for you.