There are no Ferengi espionage cards.
Only way I see they can do it on their own is with Bribery. But this doesn’t work to steal it.
investigate warp signature works it seems. But you won’t seed that unless you are already seeding Earth
Otherwise, to steal, it seems you need to Mix Selok and there are no Ferengi treaties. So TMW her?
And I guess as an aside. If I download Selok with Undercover Agent, can I say as I’m downloading her I’m discarding TMW to make her compatible with all my Ferengi?