I've seen a lot of successful dropshipping stores that include the entire size guide in each product description. I've also seen compelling arguments in favor of leaving it out of the description, so as not to overwhelm the buyer with visuals. Is there evidence to conclusively say that one schematic is better than the other?
This is something that depends on many factors like your product layout or type.
You could do a simple A/B test and see what works best for your store, your users, and your products...
With Google Optimize you can setup this test fast and not guess it.