There is nothing official, so take the thing as a simple rumor, but according to what is reported by the YouTube channel TheGamingRevolution, also reported by Game Rant, Call of Duty: Modern Warfare might contain (among others), these multiplayer modes not yet announced.
According to reports, Infinity Ward has experimented extensively with many different methods, before focusing on a certain quantity of these including the six revealed by the alleged leak. However, it is not clear if these are intended to be full details, and fixed or temporary events in the rotation of the multiplayer of Call of Duty: Modern Warfare.
A mode is called Team Defender and ricalcherebbe the one that was inserted for the first time in Call of Duty: Modern Warfare 3, with a team that needs to defend a particular member by collaborating in the game of the team. The second mode would be a change in new of Demolition, a competitive mode where there is no respawn and therefore if it is deleted you out from the game.
The other two modes are Clan Wars and Cranked, both from Call of Duty: Ghosts. Finally, there emerged information about the other two modes, one of which has been already presented, and the other which is rather unusual: the first Gunfight, already tested in the alpha of Call of Duty: Modern Warfare, and that apparently, it will host a wide range of variants that modify the game experience.
Finally, the last mode that is mentioned is the inevitable battle royale: while it was not announced, his presence is highly likely, given the trends of the market, but there is the chance that it may be thrown directly in 2020 as the title of a standalone free-to-play, with modes in the solitary, two, three, or more players per team.