Interview with Koinuma about the game, revealing some info on it.Cliffnotes here for those who don't want to click the link:
-A number of playable characters from across the manga are planned, though they won't reveal how many just yet.
-Omega Force decided to do a Berserk/Musou crossover due to Koinuma and many of the staff being huge Berserk fans.
-They decided to bring it overseas due to the fact that all their other games were coming west anyway, along with the fact that the 2016 anime is being released in the west as well.
-They chose to make a Musou-styled game because fans in Japan have been asking for one. Aside from this, the 2016 anime studio specifically asked for it to be a Musou-styled game, and Koinuma agreed since Berserk fits the mold quite well.
-The game will cover everything from the Golden Age Arc to the end of the Falcon of the Millenium Empire arc. (It's likely going to cover the Black Swordsman Arc, as well, but they just listed it in chronological order.)
-Violence and gore will be censored in the Japanese version but will be in full force in the west. On the flipside, the sexual content might be censored in the west but be in full force in the Japanese version.
-Boss battles will differ from the usual Musou gameplay, in that you will be fighting the boss alone, focusing on the fight, requiring you to strategize and dodge, etc.
-No official confirmation on which platforms will be localized, though trailers show that only PS4, Vita, and Steam are coming to the west (while in Japan they have PS3, PS4, and Vita).
-Koinuma wants to add in a playable character that no one will be expecting.