Offline values can be specified in Tracking Source and Tracking Number Google Analytics sections.If a CTM account uses offline defaults for universal analytics or 360, the data will transfer to GA4 automatically, provided that the CTM account is integrated with GA4. If you want to specify which data stream the event should be sent to, you must include the data stream measurement ID in the setup. If you do not wish to specify a data stream, simply leave it blank and the event will follow the workflow rules in the integration.
Session data hierarchy
When session data is associated with an activity, CTM will always use the true session values. If a session is NOT present, the system will look at the Tracking Number defaults first, and lastly the Tracking Source defaults.
True Session > Tracking Number defaults > Tracking Source defaults > (direct) (none)