That's what I was thinking, except the line between the two colors is far crisper than any two-tone piece I've seen. Maybe that's just due to CGI and what-not, but I can't imagine a marbled core being released.
Jawblade and Fangz very clearly have different heads. Similar in some ways, yeah, but overall quite different. And this being a prequel wouldn't work very well, seeing as Evo was either a 1.0 for a very short time, or created as a 2.0. I think these figures are very clearly updated with the 2.0 tech at least, aside from the helmets (and Breez's feet).
Also, just noticed that Breez's forearms are possibly white. That would be interesting- bone colored bone pieces. And from the backgrounds (as well as the specific modifications in the case of Furno and Breez), it's pretty apparent which Hero will be fighting which villain. Seems a little ridiculous that Rocka will be fighting Black Phantom all by himself, considering how new he is.