One of the most Google Shopping-like channels is eBay Commerce Network. Not only do the ads look identical to Google Shopping PLAs, but they are entirely feed based as well.
Getting an optimized eBay Commerce Network feed involves excellent feed management, and is crucial to performing well. The ads can show up not only on Shopping.com, but also on eBay.com, and even CNET and Consumer Reports.
There are many errors to watch out for on eBay Commerce Network, with many problems codes like missing categories, titles, brands, and even missing product matching attributes.