Koei Tecmo's CEO Kou Shibusawa mentioned it in a new interview:
Source: https://zhugeex.com/2016/01/interview-with-koei-tecmo-ceo-past-present-future/
Shibusawa then went on to talk about Ni-Oh first announced at E3 2005 more than 10 years ago. Since then they have remade the game from scratch 2 times with this being the third iteration and he hopes that third time is the charm! Theyve also finalised the concept theme to be Sengoku Dark Fantasy. The game is being developed exclusively for Sonys PlayStation 4 from the ground up and is being optimised for 1080p, 60fps.
Source: https://zhugeex.com/2016/01/interview-with-koei-tecmo-ceo-past-present-future/