New Merchant of Record application field in order object
API
Effective October 01, 2022
As of GraphQL Admin API and REST Admin API version 2022-10, information on application acting as the Merchant of Record for the order would be available through the Order object. This information would only be populated with supported applications.
New merchantOfRecordApp field in GraphQL Admin API returns OrderApp object and merchant_of_record_app_id field in REST Admin API returns the id of the application .
Learn more about the Order object on Shopify.dev.