Currently, you can set external_image_url values on product variations through an import tool, but there is no visual interface in the product editor to see or edit these.
This feature request is to add this visual interface.
Add visual interface to set external_image_url per variation
Dave Hilditch shared this feature
March 14, 2018
May 25, 2020 @ 8:12 pm
This has been implemented in beta 2.33