Recently developer Beenox, who's been responsible for helping out the various Call of Duty studios as well as making Call of Duty: Modern Warfare Remastered, posed with members of the Canadian army in a photo, leading fans to question whether a second title was in development, possibly for the Switch.
The rumour is farfetched, but now more evidence seems to point to something Nintendo-related happening with the series. For example, before the release of Call of Duty: Black Ops 3, the ability to link your Activision account with your Nintendo account was removed, and this didn't return with the release of Call of Duty: Infinite Warfare, but in a recent update made to the site on Friday, you can once more link the two accounts.
Furthermore, an anonymous source has told Badfive that a Switch version is indeed under development, and that it'll be revealed around E3. Take all of this with a pinch of salt, but it's interesting speculation nonetheless. Would it be a smart move to make the game for the Switch?