Your challenge is to have a woman in control of Rome. I'm not talking about a woman being a behind-the-scenes power, as was said to have been the case of Agrippina the Younger, I'm talking about a woman being Rome's de jure ruler.
Hadn't Byzantine (Roman Empire too) couple empress? Altough not sure how powerful they were. Perhaps there could be someone Roman version of Cixi. Or then just let Roman Empire survive much longer so there might be someone strong empress.
But Zenobia wasn't Queen in her own right legally she was just the Regent for her son.Zenobia defeats Aurelian and she decides to reunify the rest of the empire instead of independence. This is the timeline of one of my mod's ideas for Ck2.
But if she conquer rome, she can proclaim herself Augusta and his son king of Palmyra and successor of her.But Zenobia wasn't Queen in her own right legally she was just the Regent for her son.