I need to check Eyeem again then. I use Stocksubmitter (only the Windows version has all the agencies), it's really great. You can search for a few keywords and matching photos are pulled from Shutterstock, then you can select the best matches and it automatically sets the keywords. It also submits to all major agencies, but last time I used it, iStock had blocked submissions from Stocksubmitter because of their stupid policies.. All other major agencies are supported though. It's free for 33 photos per month per agency and reasonably priced above that.