No, OP asked about a Ghosting effect. That was what was being described.
Rendered skeletons currently don't interact with Unity's post-process motion blur beyond what Unity simply does on a per-object basis.
Note that the post-processing stack requires shaders that write to the depth buffer for per-object motion blur to work, so just like on Sprites for Unity's Sprite/Default shader, Spine/Skeleton will not work. You need to use a shader that writes to the depth buffer.