Hoard, a listing tool from Hoard Systems, helps a seller photograph, describe and list their own stock on eBay and Whatnot. Only the seller and the people the seller adds as users can sign in. This page says what the tool keeps, who else sees any of it, and how to have it deleted.
Photos are private: they are shown only to signed-in users. The one exception is the photo links in a listing file the seller exports for eBay or Whatnot. Each of those is a long random link to one photo, made so eBay or Whatnot can copy the picture into the listing. The links name nothing and cannot be guessed, and they ask search engines not to index them. Photos of items exported before these links existed stay reachable at their old address until eBay has the listing, for at most 30 days.