In the v1.08 release, the "DLC" characters are technically already included in the game files but often remain locked behind a software wall. You can manually unlock them by editing or replacing a specific script file:
: Blanka , Cody, Dudley , Elena, Guy, and Sakura . Street Fighter X Tekken -v1.08- All DLC -xVENOMx- The Game
Increased general damage across the board to reduce the frequency of matches ending in time-outs. In the v1
: Reduced hitbox sizes for key moves from Ryu, Ken, and Akuma to provide a fairer competitive environment. Cosmetic Content In the v1.08 release