Well Cyrax and Sektor didn't die so they will probably return. Whether fighting with Shinnok or against him is unknown due to them serving Outworld last game. I prefer Sub-zero get his humanity back though.

I think that Robot Cyrax and Sector will be back. But Robot Sub-Zero, Robot Reptile and Robot Smoke will just be alternate costumes

Robot Reptile Was Challenge Tower only

There was no Robo Smoke in the last game

Cyber-Sub Zero was a separate character.

I wonder if Cyber Subby is coming back, he was still cyber in soul form.

I think...

Sub-Zero: He'll get his humanity back

Cyrax: He'll regain his humanity too, except use some of the cyborg power he was given to his advantage and joins the SF.

Sektor: Stay a cyborg and rule the Lin Kuei

I wish so much for the Cyrax/Sektor rivalry to return. In the old timeline Sektor was clearly evil and his own faction the Tekunin spread like the Borg, while Cyrax reclaimed his humanity. Their objectives clashed which made them enemies but their rivalry wasn't as blatant as the played-out SubZ vs Scorp moras. On the other hand in the new timeline Cyrax & Sektor were shown clearly to have strong differences of opinion pre-automation. Their rivalry should be inevitable, and could lead down a new path of consequences.

I think Sub-Zero will ultimately return in human form, somehow.