UE5 is not on the horizon, if NX can run some of the UE4 showpieces without major degrades that would be a huge feat. 

It's hardly been use this generation. Aside from indie games. Tekken 7 and Street Fight V are the first AAA titles that use UE4. They currently are the only ones on the market if I'm not mistaken. Many more are coming. All but two of them on the list are from Japanese Developers, which is rather a plot twist. Those two are Gears of War 4 and Eve: Valkyrie. Fable: Legends was using it but it's been canceled. I'm obviously not including games by Epic.

https://wiki.unrealengine.com/Category:Games

Not supporting an engine like UE4 (or rather the enigne not supporting the console) is a huge deal, today more than ever before. Not only are engines like UE4 widely used and supported, they have opened up even more in the last years: Nearly all bigger engines have become cheap or free to use instead of needing to be bought for thousands of dollars. Students, self-learners, indies, just everyone can use Unreal, Source 2, Cryengine, lumberyard, unity and more today. Those people (I being one of them) will be the devs of tomorrow.
And let me tell you, not having native engine support is a HUGE deal. I already had enough problems with just getting my projects to run just on 64bit Win and thats literally the easiest thing the UE4 can do. (And I had the support of my professors and other students as well!)

To bring a game from an engine like that to a not supported platform has to be a nightmare from all I heard.
Its possible if you are really good, have a lot of people that know their shit and enough time & money, but no developer ever would do it voluntarily. Its just way to much work and trouble.

This is news? Reminds me of a thread on here a few months ago... I think that one was for the NX supporting Unity. xD

Yeah, its not used a ton yet, its still the primary third party engine, I think a lot of indie devs are using it. Its also being used for Kingdom Hearts 3 and FFVII. I Imagine its popularity will grow in the coming years.

There is no reason why it couldn't besides fees. Nintendo must realize that for most games they will have fastwr development by using pre-existing game-engines. It would probably shave off six months to a year of development time, and considering how versatile game engines are today the games won't look like clones.

guess the quote system fucked that one up. It looked right in the reply window.

Most 3rd parties are using their own engines from their publishers actually. Most indies are using Unity, but a lot of them are using UE4. It's not primary, nor is it even mainstream right now. It's mainly seeing it's success in the east. Something no one would have expected xD

By primary "third party" engine, I'm talking about engines which are oursourced. I put it over Unity because I don't know of any AAA games that are using it and Cryengine is dead atm