So it's pretty much impossible for a Guyver video game to be made, I'd consider one ever happening breaking a law of physics. But that doesn't mean we can't play around with the idea right?
So which developer would you want to handle this? What type of genre would you want?
Me, I think Platinum Games (Bayonneta and Metal Gear Revengeance) could do a hell of a job. They are proficient at making epic action games, and can do gore just as good, two things Guyver is known for. So to me, a Guyver game would be a 3rd person hack n slah game, definitely rated M. Gameplay would be about using all of the Guyver's abilities to quickly and efficiently dispense of Zoanoid threats. The more of the Guyver's powers you use, and how quickly, gets you a good rating.