There are WordPress plugins that have been developed to duplicate entire sites.You can use one of these plugins as an option to duplicate a WordPress/WishList Member site as all WishList Member settings, members, etc. are stored in the WordPress database. So, if a plugin creates a complete copy of the WordPress site/database, it should include all the WishList Member settings, members, etc.
We have not developed these plugins but the Duplicator and WPvivid Backup plugins both have higher user ratings. Additional options can be found in the WordPress plugins directory.
These types of plugins can be used to create a full copy of your WordPress/WishList Member site if you would like to transfer that site to another URL.