WooCommerce lets you manually export your products, but unfortunately, this does not pull any variant products at the child level, and instead only gives you product attributes for the parent products.
Well optimized WooCommerce feeds are essential for performing well on Google Shopping. Feedonomics has a WooCommerce Product Export plugin allows you to easily get up and running on Google Shopping, Bing Shopping, and hundreds of other channels.
See how Feedonomics can take your WooCommerce products and get them on Google shopping as easily as possible.