I'm not aware of any such metric. Every industry and every product type, is going to be very different. Someone buying a replacement bath plug will look at the page for long enough to make sure it fits their plug hole. Whereas someone buying a computer or a chandelier may look at a page for a lot longer and they may go away and come back again. This could also make bounce rates/conversion rates tricky as the plug displayed with very little information and a basic picture may have a shorter dwell time and a higher CTR than the computer displayed on a page full of very useful specs and beautiful pictures and videos.
A good way to approach an e-commerce project is to take a snapshot of current performance metrics, focus on engagement and UX improvements and then re-record performance.
An anecdote for you:
A former e-commerce employer of mine began using a third-party service that used the popularity of products based on views to make product suggestions to other customers. Unfortunately, the site had serious products that people bought and used, as well as products that were mouth dropping and very shareable but not often bought. We had to get the company to customise the service to be based on actual purchases.
The point of the story: even though e-commerce stores often share much in common and will often benefit from some of the same basic patterns and approaches, they can be like comparing florists and chemists or jewellery shops and newsagents.