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Per my experience, SharePoint 2016 Update may not be available via SCCM/WSUS. A similar thread for your reference: SharePoint Updates Deployment via SCCM
The answer from @Alzoo :
I asked the same question to MS Support, it is not available via SCCM. This was their answer.
We cannot deploy the farm-deployment update using software update function via SCCM. This behavior was by design since SCCM doesn't sync Farm update.
Had a word with Sharepoint engineer:
Sharepoint updates itself are usually farm updates which means that you deploy it one sharepoint server and then use sharepoint itself to further deploy it. This is something you cannot handle with the updates deployment feature of SCCM.
Thanks for your time. Have a nice day!
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