Customised version of the Common Maps feature found in the Lyra game sample from Epic Games.
There's two ways to add maps, either via the included settings UI found in Project and Editor settings or by editing the DefaultEditor.ini and DefaultEditorPerProjectUserSettings.ini.
DefaultEditor.ini example:
[/Script/CommonMaps.CommonMapsProjectSettings]
+CommonMaps=/Game/SCPCB/Maps/Entry_P.Entry_P
+CommonMaps=/Game/SCPCB/Maps/TheSite_P.TheSite_PDefaultEditorPerProjectUserSettings.ini example:
[/Script/CommonMaps.CommonMapsUserSettings]
+CommonMaps=/Game/SCPCB/Maps/Dev/Dev_Interaction_P.Dev_Interaction_P