The External Membership Sites Add-Ons Bundle allows you to sell external MemberMouse levels and bundles through your WooCommerce store, so when a customer purchases a WooCommerce product, he is also registered as a member on your MemberMouse membership site.
In this video we go over how to easily sell external memberships that are located on a different website than your WooCommerce store using the External Membership Sites Add-Ons Bundle for the MemberMouse WooCommerce Plus plugin: