We recommend using WP All Import to import products to WooCommerce, but ANY import tool can be used.
For external images to work, follow these two important steps:
- Do not import ‘media’ – i.e. whichever import tool you are using, pretend as if there are no images for the products
- Import the image URLs to a meta field called external_image_url
Then there are no actual images imported, only the image URL (to the meta field).
External Images Plugin then adds filters to the relevant locations for the featured image to ensure WooCommerce and WordPress pulls the image URL from the meta field instead of from the normal media field.
You can also find a guide to the External Images Plugin here: