Yes, you can have any combination of subscriptions

Free, Pro Monthly, Pro Annual, and Lifetime subscriptions can be applied to any of your sites. Each of your sites is able to have a different subscription designation.

To upgrade a free site, navigate to the Pro tab in your dashboard while viewing that site in your Sites List and select the subscription that fits your needs.

🌟If you subscribe to additional annual subscriptions, you will be subject to Apple’s prorated billing structure. Read more about that here.

🌟To see a list of all of your current subscriptions, you can view them with Apple here.