Computer Configuration > Administrative Templates > Microsoft Edge > Identity and sign-in
Both
HKLM\Software\Policies\Microsoft\Edge
Allows Microsoft Edge to switch to the appropriate profile when Microsoft Edge detects that a URL is the intranet. If you enable or don't configure this policy, navigations to intranet URLs will switch to the most recently used work or school profile if one exists. If you disable this policy, navigations to intranet URLs will remain in the current browser profile.