Having a disguise hides what a ship is when it is targeted directly. However, the ship shows up with the regular race on the battle tab and in the legion roster. So if a ship has a disguise, a quick click on their legion name will reveal their race.

I am assuming the same is true of the dark smuggler's chassis, but perhaps someone with such a player on their BT can verify whether they show up as a Dark Smuggler on the BT or their real race/occupation.