Thanks for your response.
It seems that Microsoft has already added the new SharePoint Server 2019/Office Online Server product menu in WSUS console. But there is no such Official Document from Microsoft right now. I'm not sure whether there will be some changes in the future. In fact, the Products and Classifications menu will be updated when the WSUS server sync with Microsoft Update Site. Please wait for several days and confirm whether there will be official released document.
In addition, I noticed that the Office 2019 updates also added into the Microsoft 365 Apps/Office 2019/Office LTSC product menu. Here is screenshot in my lab for your reference:
Please help to confirm whether the phenomenon is as the same as your's.
Also here is product menu screenshot for your reference:
Thanks for your time and have a great weekend.
Regards,
Rita
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