If you have admin permissions on multiple Vault accounts, you can use high-resolution Lightbox or Collection links to import those assets into another Vault account to which you have uploading permission.
First, create a new Upload Set, or navigate into the existing Upload Set where you want the new assets to be imported. Once inside the Upload Set, you'll find the option to Import via Vault URL:
Which brings up the Vault URL Import modal. Paste the high-resolution Lightbox or Collection link and enter the password, if one exists:
When you click the Begin Import button, you will be taken to the Upload Set's Import page where you can see the progress of the import:
