After searching for hours.. I finally found some CWCheat codes for Tekken 6
Well, here are the codes:

_S ULUS-10466
_G Tekken 6 [US]
_C0 Inf. HP
_L 0x004078C2 0x000000FF
_C0 Instant Kill
_L 0x204081F0 0x00000000
_C0 Instant Win Player 1
_L 0x204081F0 0x00000000
_C0 Max Gold
_L 0x213DFD6C 0x05F5E0FF
_C0 P1 Play As Azazel P1 Skin
_L 0x603FDAF0 0x00000044
_L 0x00020003 0x00000168
_L 0x200002D4 0x2000012C
_C0 P1 Play As Azazel P2 Skin
_L 0x603FDAF0 0x00000044
_L 0x00020003 0x00000168
_L 0x200002D4 0x2000012C
_C0 P1 Play As Nancy P1 Skin
_L 0x603FDAF0 0x00000052
_L 0x00020003 0x00000168
_L 0x200002D4 0x2000012C
_C0 P1 Play As Nancy P2 Skin
_L 0x603FDAF0 0x00000053
_L 0x00020003 0x00000168
_L 0x200002D4 0x2000012C
_C0 P2 Play As Azazel P1 skin
_L 0x603FDAF0 0x00000044
_L 0x00020003 0x0000016C
_L 0x200002D4 0x2000012C
_C0 P2 Play As Azazel P2 skin
_L 0x603FDAF0 0x00000045
_L 0x00020003 0x0000016C
_L 0x200002D4 0x2000012C
_C0 P2 Play As Nancy P1 Skin
_L 0x603FDAF0 0x00000052
_L 0x00020003 0x0000016C
_L 0x200002D4 0x2000012C
_C0 P2 Play As Nancy P2 Skin
_L 0x603FDAF0 0x00000053
_L 0x00020003 0x0000016C
_L 0x200002D4 0x2000012C
_C0 Stop Timer at 60
_L 0x208FBE4C 0x00000E11

Just copy and paste it in your cheat.db
Credits goes to Google