Outlook 2016 for Mac uses the term Profiles not Identities. A profile is a set of email accounts and user settings. Outlook Profile Manager is a tool included with Outlook 2016 that allows users to create, delete and set default Outlook Profile.

To access Outlook Profile Manager:

  1. Open the Finder menu, and navigate to Applications.
    Finder
  2. In the Applications window, press Control key and click Microsoft Outlook, then Show Package Contents.
    Package Contents
  3. Expand folders Contents > SharedSupport > Open Outlook Profile Manager.
    Outlook Profile manager

You can perform the following actions in Outlook Profile manager:

  • To create a new profile, click on Add icon Add Profile and type the name of the new profile.
  • To rename a profile, double-click on the profile and then type in the new name.
  • To delete a profile, click the profile that you want to remove to select it and then click on Delete icon. Delete Profile
  • To switch between the profiles, click on the profile you wish to use > Action > Set as Default. You must restart Outlook for the changes to take effect. 
    Change default profile

Note: it is not possible to configure Outlook 2016 for Mac to prompt for a profile to be used during startup. You can only switch between profiles in Outlook profile manager.