Check for duplicates across multiple workspaces

It would be really nice if there was a feature that would check for duplicates across all or chosen work areas instead of the current work space. Also when reviewing transactions that come in from bank, I would appreciate if it could find transactions in any (multiple) work areas already there. Eg. I go to the store and scan the receipt and later that day or next day, the same transaction comes in for review and I would like to be able to merge the 2 keeping the receipt already scanned in. I usually scan and toss, so it becomes a problem creating duplicate transactions sometimes across work areas.