Hello,
Is there a way in which we can setup managed previews on an employees iPad. We ideally want it to never show the Preview of say Microsoft Teams, Messenger, iMessage etc.... it’s always shows what message has been sent to the employee on the iPad lock screen and we want it just to say “Notification” from specific app.
There's a notifications payload for mobile device configuration profiles. Haven't used it much myself. 
There are notifications and restrictions payloads, however Apple doesn't seem to support suppressing the actual message preview in either. That would be a good feature request!
https://developer.apple.com/business/documentation/MDM-Protocol-Reference.pdf
try turning off the Restriction 'Show Notification Center in Lock screen'
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