Please note that a WishList Member license does not contain any data.
If you want to transfer any data from one site to another site, you will need to transfer that data to the new site.
All WishList Member data, member info, etc. is stored in the WordPress database so you would need to transfer any data you want to keep from the old site to the new site.
The WishList Member license key allows you to activate WishList Member on a WordPress site. But it does not contain any site data.