The events are pulled from Event Log as they are in the log.
If you click the details tab in the event and switch to XML view, you'll see what the raw event really looks like in the log.
The view in the opening view is already rendered by appropriate DLL for this kind of log.
Often there is no string representation of the event at all in the event itself. Sometimes some entities reported in the event will have english names. Sometimes they will be in proper local language. It varies.
There is no such information in the event itself so just by pulling raw events from event log - no. You could manually define a calculated field in splunk but that would require quite a lot of work and would obviously only covet the cases known beforehand.
Maybe, but I'm not an expert on windows here so it's a great "maybe" you could pull rendered events using custom script or program but then you'd get the data in format not conforming to that which Add-on for windows expects.
It's simply that when working with windows events you usually search for event codes (regardless of whether you use splunk or any other tool).