Within a tenant that is synced via Azure AD Connect with an on-premises AD it is possible to enable password writeback if you met some requirements (have needed license, configured Azure AD Connect, enabled option in Azure).
Within the Azure Portal this state can be checked and be changed and it uses the following Azure API call: https://main.iam.ad.ext.azure.com/api/PasswordReset/CheckWritebackConnectivityStatus
Unfortunately this call can't be done by myself, cause I don't have a valid token for this endpoint. So exists there any similar call within Graph (v1.0 or beta) to check if writeback is enabled or is it possible to get a valid token for this endpoint?