In ST:DIS 3x13, Osyraa
has taken control over Discovery and is attacking Starfleet HQ from within its defense perimeter.
She knows that "the primary shield emitter is disguised as a secondary deflector array."
How can she know that?
Does she have a mole inside Starfleet? Note that she did not even know where Starfleet's current HQ is located and probably neither what it looked like until shortly before.
We are not given much information. There are, as far as I understand, two possible explanations for her saying that:
She has a mole or tortured someone who knows or someone else did within her vast network of couriers, ie. through intelligence in the form of espionage.
She made a good guess based on strategic thinking. Since the primary shield emitter could not be located, a deflector array is essentially a shield emitter, and it would be foolish to hide an essential primary system as another essential primary system, hiding the primary shield emitter as a secondary deflector array simply makes sense. Otherwise, it would be much harder to guise the very specific energy patterns emitted. Maybe she even encountered these tactics elsewhere. This explanation would mean she did it through intelligence in the sense of good thinking, which certainly isn't beyond her.
She seems very sure of herself up to the point of being bored, which speaks for the former explanation. But then again, her character is portrayed in a way that she could equally well seem more sure of herself and bored the closer she gets to gambling. Her negotiations with Vance had it both ways.
As @ThePopMachine rightfully pointed out, Osyraa's crew had gained
Full control of all the ship's systems, apart from a very small subsystem (which probably is where the sphere data hid). Burnham does tell Osyraa she should check the logs for the course to the dilithium planet. This may indicate that she simply gained that knowledge from the ship's databases via her command codes.
