@Ruin:
Considering the lot of fighting styles in One Piece are, like, completely character exclusive
I can't really see a create-a-character kind of thing working out
that said, I would jump at the chance to make myself a sexy lava woman with a bomb-ass facial scar
nod A normal "Create a Character" is likely never going to happen in a game like the Warriors games. But, if the PC version can be modded I would just need to find people I could commission to make her for me. Would probably get expensive, though, since I would need pre and post Time Skip models made, her own unique move-set, and voice. If I had the money, though, I'd gladly do it. It would be fun to run through the story as my OC.
@Green_vs_Red:
No one told that to Namco-Bandai when they made Xenoverse.
That's a bit different a thing, though. DBZ characters often have similar moves, so it's pretty easy to offer up various abilities to choose from for a character you make in that game. Offer up some various outfits and hairstyles seen in the series, and you're good to go. A Pirate Warriors CaC wouldn't work as well, as every major character in One Piece has their own completely unique moveset. I would never be able to come close to making Emiin that game even if they offered CaC. She fights using a flail and whip, with some Fishman Karate thrown in. She has her own unique attack names and styles, and her own unique design that I could never recreate with any amount of pre-set items the game could possibly offer. That's not the same in the Xenoverse game, though. I won't be able to get my OC, Ameli, to be PERFECT, but I should be able to get her main fighting outfit easily, since it's similar to that of Goku, Yamcha, and Krillin. She also can get her major attacks easily, since she uses some of the same ones Krillin uses. The only thing Xenoverse will really be missing is Ameli's hairstyle, since nobody else in DBZ has ever had it before.