Currently External Images only works with featured images. This feature request is to add ‘gallery’ support so that ALL images on sliders, carousels and in the gallery can be made external.
This will need some careful thought to replicate exactly the behaviour of the gallery and store the ‘images’ array/collection somewhere against the product data.
This has been implemented
How do I use this feature? I can’t find any information on it in the user guide or FAQ.
Import the gallery image URLs to the eigallery meta field.