An update is being deployed on Intune to allow you to manage Outlook Mobile settings (such as Focused Inbox, sync contacts…) for iOS and Android.
To start implementing this application configuration, logon to your Intune portal (either from Azure portal and then going to Intune or from the Device Management from Office 365 portal)
Then go to the Client apps configuration blade and create an App configuration policy
Select the enrolment type, platform and associated app (in this case Outlook)
Then in the Configuration settings blade select Use configuration designer and set the various settings as you want/need
You can also complete the configuration using Configuration Keys is needed (check https://docs.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/outlook-for-ios-and-android/outlook-for-ios-and-android-configuration-with-microsoft-intune#configuration-keys for details)