Members plugin > optin Mailchimp list ??

I manually add users with cvs import from woocommerce import and bulk import orders in order to ease the participate process for new learners.
Last step is to manually link those new members to a specific membership in order to mail them based on their status (participating or alumni student). But when adding new members to a memberlist it's not being picked up by Mailchimp list.
Or is the subscription soly being triggered by new users?