A new Group Policy Object for Microsoft Edge in Windows 10 Creators Update allows you to set a default search engine for all users.
This can be set for the Computer or User context and is located at:
Administrative Templates\Windows Components\Microsoft Edge\Set default search engine
NOTE: This setting is only available for Windows 10 Creators Update (1703) or later.
Looking for an awesome, no-nonsense technical conference for IT Pros, Developers, and DevOps? IT/Dev Connections kicks off in San Francisco in 2017!