Network Locator uses ArcGIS Pro Print Layouts for producing the PDF map document. You can use all of the out-of-the-box features that ArcGIS Pro Print Layouts offer.

Additionally, you can pass custom text variables to the print layout. This is done by configuring the field vertigis.network-locator.print-output.dynamic-print-elements (check Print Output Configuration)

Example:

"dynamic-print-elements": {
             "orgname_value": "VertiGIS",
             "request_id": "{request_id}",
             "request_purpose": "{request.purpose}",
             "user_company": "{user_data.attributes.company[0]}",
             "user_name": "{user_data.firstName} {user_data.lastName}"
           }

These text variables can then be placed on the ArcGIS Pro print layout as a Text Element, as shown below.