Multiple objects are drawn in a single ase file, and the objects are separated into individual layers.
The example of layer condition is as below.
-object1
-object2
-object3
-shadow
Thanks for reply. @dacap
Resolved by exporting shadows one by one.
But what I wanted was to export automatically with shadow no matter how many objects I had. In the example above, only object3 was expressed, but the cli command remained unchanged even if object4, object5, etc. were created. -layer and -ignore-layer are not functions that I wanted because the cli command changes as the layer increases.
In that case you might find useful the Lua API and running a -script (they can be executed from the CLI). So you could iterate the layers and hide/show each one and then save the sprite each time.