Not in 1 year it wouldn't. Again, I don't think some of you guys realize this. You CANNOT build, bug test, and prepare an entirely new feature rich engine in a single year. Its just not going to happen. As long as WWE demands its one game per year, you won't be seeing a new engine made instead of building on the previous one.
Its like trying to build a five star hotel in the span of 3 hours, its just not going to happen no matter the manpower you have without cutting a *censored*load of corners and making a deathtrap.
Nevermind that EA would probably try to force whatever poor developer they force the game on to use Frostbite which would be an absolute disaster.
Madden have gone through two or three engines in the 2010s without skipping a beat. Frostbite is also not that bad. A WWE game under the Frostbite engine would at least be developed to not auto crash because of a year change.
Frostbite was built and designed for shooters and has been repeatedly pointed out to be a huge pain in the ass for games other than shooters to develop for, and is one of the reasons Bioware developers despised working on Inquisition.
Madden is also a MUCH different game from a WWE game and, no offense to football fans, trying to compare the two is a bit like trying to compare apples to TV projectors, there's no similarity there.
Also, when you say "had 3 different engines" are you saying they made 3 different engines completely from scratch? Because somehow I very much doubt that. Built and redesigned the previous one maybe, but creating three different engines for the same series in the span of one decade would and should be considered INCREDIBLY wasteful of resources.
Madden has gone from whatever they were using till 2012 to Ignite from 2013 - 2016 to Frostbite in 2018 and beyond, all in one decade.
Frostbite being designed for shooters hasn't stopped it from being a functional engine for FIFA, Madden, Need for Speed as well. Worst case scenario it would use the Ignite engine like NHL still does, an engine that was created for sports use, so it's not even a forgone conclusion that EA would "force" anything on anyone. Not sure Bioware, the company whose ego was the biggest reason for the disaster that is Anthem, is the best example for Frostbite being "an absolute disaster" for other games too.
An EA game released with either engine would be released in better condition than 2K20 was while being more supported with patches post release than we've seen from 2K20 or any WWE 2K game for that matter.