Hey there, the team is working on bulk movement between items already in an organization collection.
If this is a new vault, you can always import into your individual account and bulk move from there, or condition the CSV prior to import (just be aware that if you export/import you will lose some vault info like attachments and password history.
Vault exports will not includefile attachments, items in the trash, password history, or Sends.
Hey there, enhancements are planned but I don’t have an ETA at this time. To avoid duplicates you can purge your vault first (be sure to have a backup stored safely, use at your own descretion) and delete collections prior to importing.