There's some other misinformation in that video (Trish being a secret playable character since the first game, DMC 4 PC coming out 'a couple' of years ago), so I wouldn't give it much thought.
Having a playable Sparda would be interesting though, simply to answer the question of how he would fight. I mean, they could very easily just give him Yamato, Force Edge (or Sparda), and Luce & Ombra without changing the movesets at all and just say 'there, we did it, now stop whining'.
However, a dynamic moveset built around the Sparda sword's morphing capabilities and the dragon form could be interesting enough to provide something new. They could make the Sparda sword into a Scythe and Axe, much like DmC did with Rebellion, while giving Yamato very different moves.