I hope there will be, but I'm not incredibly certain if it'd fit in the way they're doing it- unless Enter becomes the sixth, or something...
There's nothing definative yet, but the best I could think of is a black armored commando-type Ranger. If Enter does become #6, though, maybe the fact that he wears white & chose white as a central theme for his BC-04 copy means that he'll be white?
While writing this, I just came up with a great one- What if Enter creates his own Ranger tech to combat the Rangers? He's already built a zord, so why not build a whole system?