Regarding the Fast&Furious/Gamer/Death Race/Crank shared universe and how Jason Statham couldn't be playing Chev Chelios if he was also playing Deckard Shaw:
Obviously somewhere in the timeline, Shaw used the Face/Off technology to switch faces with Chev Chelios, meaning sometime chronologically before Gamer, there was a F&F and Crank crossover sequel where Chev and the Furious crew teamed up to get Chev's face back from Shaw called Furious Crank.