The long awaited and requested Azure Active Directory (AAD) administrator role is now available in preview: Authentication Administrators.
The Authentication Administrators role can manage authentication process for end-user, like manage multi-factor authentication (MFA) requirements for end-users (from activating to revoke the ‘remembering device’).
You can manage Authentication Administrators role membership from your Azure AD (either from the Azure portal https://portal.azure.com or the AAD portal https://aad.portal.azure.com/) using the Roles and administrators configuration blade
This not yet (??) available from the Office 365 administration portal.