Hello, you can import all your animations in a single skeleton if the names of the bones, constraints and attchments belonging to an animation match. If they don't they won't be imported.
您好，如果属于动画的骨骼、约束和附件的名称匹配，您可以在单个骨架中导入所有动画。 如果他们不这样做，他们将不会被进口。

To do so choose Spine>Import project>Animation and select the animations from the project you with to import.
为此，请选择 Spine>Import project>Animation 并从要导入的项目中选择动画。
Import - Spine User Guide: Project

You will then be able to export the skeleton with all the imported animations as usual.
然后，您将能够像往常一样导出带有所有导入动画的骨架。
Export - Spine User Guide