User Configuration > Administrative Templates > Microsoft Word 2016 > Disable Items in User Interface > Predefined
User
HKCU\software\policies\microsoft\office\16.0\word\disabledshortcutkeyscheckboxes
This policy setting allows you to disable specific shortcut key combinations in the specified applications. If you enable this policy setting you can disable specific shortcut keys for the selected application. The predefined list of shortcut keys you can disable becomes available to you when you enable this policy setting. If you disable or do not configure this policy setting, the predefined list of shortcut keys are enabled for the application.