Transfer Stashes
shortcutyt, object mode
The Transfer Stashes tool is used to copy stashes from one object to another one.
Existing stashes on the target object will not be overwritten. The transferred stashes will simply be added to the existing collection.
Selection
Exactly two objects, where the inactive object carries stashes.
the sphere one the left is active and will receive stashes from the sphere on the right, which was selected first