How do I create a person type like "Partner contact" to use as a resource instance?

Summary:

We need to create a new resource instance, but the person type cannot be either employee or contingent worker because that consumes HCM licenses; therefore, we want to use "Partner contact".

Content (please ensure you mask any confidential information):

How do I create a resource instance with the person type "Partner contact"? I've tried creating it from the "Contacts" screen in the Service module, but it still doesn't appear in the list.

What we need to associate here are the field service technicians who will use the Oracle Field Service app, but they are not company employees.

Version (include the version you are using, if applicable):