Hi @Kumkuse
Thank you for reaching out to the community forum!
For your query I understand that you would like to know is it possible to enable hybrid Microsoft Entra ID join without AD Connect sync when the organizational unit is not in the sync scope of AADC.
To answer your question, it is not possible to enable Hybrid Microsoft Entra ID join without Microsoft Entra Connect sync, because hybrid Microsoft Entra ID join relies on Microsoft Entra Connect to synchronize computer objects from the on-premises Active Directory to Microsoft Entra ID.
Without synchronization, the computer object will not be available in Microsoft Entra ID, and the device cannot be Hybrid Microsoft Entra ID joined.
To enable Hybrid Microsoft Entra ID join, it’s necessary to configure Microsoft Entra Connect to synchronize the computer objects from the on-premises Active Directory to Microsoft Entra ID.
Hope this helps. Do let us know if you any further queries.
Thanks,
Akhilesh.
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