Imo, the characters who made an appearance as a cameo, but didn't make the cut for the roster (such as tanya, shinnok, etc) will be in MK10.
Maybe like hints?
So we have
-Tanya
-Frost
-Li Mei
-Shinnok
-Meat
- Kira
- (Sareena via Vita)
-(Tremor via Vita)
- Hopefully Skarlet can finally establish a role in Mortal Kombat's main background now
It kind of makes sense if MK10 should follow the mk9 story mode, you know, all the females in the list will replace Jade, Sindel, Kitana, etc.
It'll be interesting to see what happens,