As an admin, how to stop notification emails when a comment is added to a users document. (not the individual onedrive settings)

I understand that you want to disable OneDrive notification emails when a comment is added to document for all users programmatically.

Unfortunately, SharePoint supports programmatically disabling all OneDrive notification emails but not supports only disabling OneDrive comments notification emails for all users.

To disable all OneDrive notification emails, go to Settings in the SharePoint admin center -> Notifications setting for OneDrive -> Clear Allow notifications.

Reference:

https://learn.microsoft.com/en-us/sharepoint/turn-on-external-sharing-notifications

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