Computer Configuration > Administrative Templates > Microsoft Edge
Both
HKLM\Software\Policies\Microsoft\Edge
This policy determines if a user can remove the Microsoft Edge profile automatically signed in with a user's work or school account. If you enable this policy, a non-removable profile will be created with the user's work or school account on Windows. This profile can't be signed out or removed. The profile will be non-removable only if profile is signed-in with either on-premises account or Azure AD account that matches OS sign-in account. If you disable or don't configure this policy, the profile automatically signed in with a user's work or school account on Windows can be signed out or removed by the user. If you want to configure browser sign in, use the 'BrowserSignin' (Browser sign-in settings) policy. This policy is available only on Windows instances that are joined to a Microsoft Active Directory domain, Windows 10 Pro or Enterprise instances that enrolled for device management. From Microsoft Edge 89 onwards, if there is an existing on-premises profile with sync disabled and machine is hybrid joined, it will auto-upgrade the on-premises profile to Azure AD profile and make it non-removable instead of creating a new non-removable Azure AD profile. From Microsoft Edge 93 onwards, if policy 'ImplicitSignInEnabled' (Enable implicit sign-in) is disabled, this policy will not take any effect.