If you want to replay the previous combats, go to your personal quarters aboard the Eos, use the "Intercom" option and you will have a new "Combat Simulations" option.
I don't have the option to replay anything. I haven't been able to access combat so there isn't actually anything to replay. I was able to speak to Ann and speak about combat, but there wasn't any sort of follow up. The only options I get when going to visit her are normal talk/massage choices. That's why I questioned whether I was doing something wrong