我也在这个论坛帖子上发布了这个答案：
How to bind one skeleton to a bone in an other skeleton?
我在下面再次发布它以包含翻译。
I have posted this answer on this forum thread as well:
How to bind one skeleton to a bone in an other skeleton?
I'm posting it again below to include a translation.

骨架附件尚未实现。 但是，根据运行时的不同，有多种方法可以让一个对象跟随骨骼。
Skeleton attachments are not yet implemented. However, depending on the runtime, there are various ways to let one object follow a bone.

如果您使用的是Unity运行时，可以使用BoneFollower让GameObject跟踪骨骼位置，然后您可以将武器骨架GameObject设置为此BoneFollower对象的子对象。
If you are using the Unity runtime, you can use a BoneFollower to have a GameObject track the bone location, and then you can set your weapon skeleton GameObject as child of this BoneFollower object.