The Basics
WordPress Import Export plugin provides a number of options for Import images. Watch the video below for an overview of a few different ways to import images.
For each record in your file, WordPress Import Export plugin will create a post or any other data, import the images associated with that record to the post’s Media Gallery, and optionally set the Featured Image.
Handle Existing Images
When import any data, you can specify the settings for importing your images in Step 4.
To add images to an existing data, check Handle Existing Items -> Update Existing items data -> Choose which data to update -> Images .