A shared product link usually gets its title and description from page metadata. The og:image is separate. If that image is just the product photo, the sale may not be visible in the image.

FastOG for WooCommerce generates product images with the current price, original price, and calculated savings. The Black Friday template is included in the permanent free Community tier, which covers up to 100 store items. Paid plans are optional for more coverage and templates.

https://preview.redd.it/kqo5rylf5pwh1.png?width=1200&format=png&auto=webp&s=1789cfd0086b7255cbfeed09a116465900449db6

It uses sample data; the “before” is an illustrative mockup.

I’m the developer of FastOG. The plugin is on WordPress.org. Would you show the discount, the sale price, or both in your product image?