If it already happened
Someone is using my photos on eBay
A listing on eBay is using your Etsy photos. Do these three things before you pay anyone who emails you offering to handle it.
Save the page. Copy the link, take screenshots, and write down the date. Your original Etsy listing, and the files you uploaded, are the proof the photos are yours.
Report it on eBay's own form. You have to sign in, and you have to be the rights holder or their agent. Start at eBay's VeRO page and use Report via VeRO Portal. Paste the copied listing links and point at your Etsy listing as the original. Temu, SHEIN, and Amazon have their own forms. Use those, not a random email.
If Etsy removed your listing because the copy showed up first, write Etsy and show them your original files and the date you published.
If it was Temu, start here. If it was SHEIN, start here. If it was Amazon, start here. If it was another Etsy shop, start here. If it was AliExpress, start here. If it was Walmart, start here. If it was TikTok Shop, start here. If it was a Shopify store, start here. If it was DHgate, start here. If it was Pinterest, start here. If it was Redbubble, start here. If it was Society6, start here. Want to see if one listing's main photo turns up somewhere else? Check it free. No account. If you want us to keep looking, the first 14 days are free, up to 5 listings, no card.