War Machine almost had another new suit to wear in Black Widow was leading. Unsurprisingly, he then continued to suit up to help the team once they reformed in an effort to make one more attempt to undo The Snap.
Rhodey may have suggested using time travel to go back and kill Thanos as a child, but that wouldn't work with War Machine teaming up with Nebula to retrieve the Power Stone from Morag. Once they were successful, 2014 Thanos still attacked them and ruined War Machine's armor in the process. He ed the final battle in a new suit, but Avengers: Endgame almost gave him another one.
As revealed by concept artist Phil Saunders in The Art of Avengers: Endgame, War Machine was going to have three different suits in the movie. Instead, Rhodey wore two suits in the film: the Mark VI costume after The Snap and the War Machine/Iron Patriot Mark VII during the final battle.
"War Machine was an interesting process because at the time when we were working on it, there were going to be three War Machine armors. There was going to be the Mark III armor from Civil War that he crashed in, which was going to be fixed. The Mark IV was going to be used to go back to Morag, and there was a whole sequence where he was underwater. That suit was going to be featured heavily there, and then it was going to get dissolved away by the acidic water - which would lead him to have to put on another suit, the Mark V, which we were calling the cosmic War Machine armor, which was going to be used for battle in space."
There are a few intriguing tidbits about another version of Avengers: Endgame that comes from this reveal. For starters, the idea of Rhodey getting back in the Mark III armor would be a fascinating addition to his arc. He already struggled to suit up again in the first place, but putting on the suit that he nearly died in could've added some layers to Rhodey's story. What we don't know is why this suit would need to be fixed for him to wear.
We've known about the changes made to the Morag sequence to Avengers: Infinity War being completely dissolved - and possibly him along with it. In the movie though, it was the Mark VI armor that War Machine wore to Morag.
Additionally, the details on the Mark V armor may reveal a completely different third act for Avengers: Endgame at one time. If Saunders and the development team were referring to it as a cosmic armor, that would imply that it was going to be featured in space. The entirety of Avengers: Endgame's final battle takes place at Avengers HQ, but other ideas were surely discussed. That said, it is possible that the War Machine/Iron Patriot suit is built for space and just wasn't utilized in that way.
