According to a project administrator working on Sekiro: Shadows Die Twice, FromSoftware is aiming to include Japanese audio in every version of the game.
Chief project administrator Bob Simpson, who works in translation and interpretation, replied to a fan on Twitter who asked if European players could use the game’s native Japanese audio with English subtitles. Simpson responded “The plan is to have JP audio as an option in every version.”
The plan is to have JP audio as an option in every version.
— Bob Simpson (@bobiodon) September 10, 2018
Source: IGN.com Sekiro Aiming to Support Japanese Audio Worldwide