Again, perfectly doable especially in handheld mode. If you would like to discuss what was implied by MS, we can look to their statement. Here is an excerpt "Microsoft has entered into a 10-year commitment to bring Call of Duty to
@nintendo following the merger of Microsoft and Activision Blizzard King." So if we are talking about specifics, the language used does not imply one way or another if it would be a port or a cloud version. Regardless, that was just one piece of my statement earlier, and personally I believe the plan was to indeed develop a bespoke switch version that was feature and content complete, just using different rendering methods. I assume one can divorce the game code from the rendering method so I do not see how this would be an issue.
Of course, I'm just trying to have a conversation as none of us here on Gaf will ever know their true intentions. That is unless MS successfully appeals the decision. (I don't think they will be successful personally)