lingxi Perhaps you are experiencing the issue where the RGB colors of transparent pixels are not being saved, as explained in the video from 04:50 to 05:55:
【[spine-unity] 常见导入问题解答】 【精准空降到 04:50】 https://www.bilibili.com/video/BV1BD4y1Y7By/?share_source=copy_web&t=290
I suspect you may be using pre-multiplied alpha (PMA) textures. If so, I think that the images used for replacement must also be PMA images in order to be rendered correctly. Alternatively, you can pack the images used in the skeleton as straight alpha textures. That way, you should be able to use the images for replacement without having to modify them. If you are not familiar with the difference between PMA textures and straight alpha textures, please refer to the following section of the spine-unity runtime documentation: spine-unity 运行时文档 资产 进阶操作 - Premultiplied和Straight Alpha导出
