You can't change the properties of anther's PIC online unless it's on your site. in which case. you download the PIC , edit properties and replace the original PIC on your site = Pirating.
Microsoft Properties can do this and using a site password you can replace the Pic. Other then ExifToolGUI will do it online providing you can log on to the site with editing privileges.
If you can't log on, you can down the PIC from any site and change the properties to whatever you want and basically claim ownership and upload it to your site, but then that is what I've said is "Pirating".