We are not able to find any API that can get Applicant Status Set ID and its underlying list of Statuses that we see in "Edit Application Status Configuration".
We have checked KBA 2879453 which explains the limitation to get Status Set ID & its statuses.
Could you please help to confirm if this limitation continues as of today or if there is alternate API facility that can help to give all Statuses of Status Set ID.
Currently, on the system, we don't have any entities representing the Application Status Set configuration, and we don't have a way to pull out the set of fields that compose the Applicant Status Set.
If you feel that this functionality is something that would be necessary for you, and would like to see that on the product in the future, we encourage you to have this submitted on the Influence portal, Please check the article 2090228 for more information.