When you are using the Bulk Edit Metadata tool and accidentally mark all of the selected assets as Accepted or Rejected, you can undo this action while you’re still in the edit modal by using the Mark None category.
Undo Asset Rating / Mark None
Click “Mark None” in Curate.
Click Update.
This will maintain the pre-Bulk Edit curation state of each of the selected assets, so rejected assets will revert and approved assets will hold onto their status.