https://www.gamespot.com/articles/heres-why-dragon-quest-11-on-switch-is-so-far-off/1100-6458028/

Dragon Quest XI is coming this year to PC and PlayStation 4, but the Switch version could be next year or beyond. In an interview from PAX East, game producer Hokuto Okamoto explained just what's happened to set the Switch version so far behind. It appears to be a case of the game needing some elbow grease to work with its engine.

"It's true that the Nintendo Switch version is under development at this moment in time," Okamoto said via translator. "Specifically with regards to the development, this game was developed on the Unreal Engine, but the version for Unreal Engine needs to be updated, I suppose, in order to support Switch. In that sense, the development is still expected to take a very long time. It's still a long ways out."