I think they're using the word 'riposte' as description/adjective - not as a comparison to the stunt.
They are basically saying that you can use deceit as an attack skill for social conflict. (like using weapons for a physical conflict)
The draw-back to using deceit instead of a skill like rapport is, if you fail to win, you will get caught in the lie. Which can turn out worse for you if you simply failed to persuade them with the truth.
Deceit works better as a defensive skill (false face forward)because you can apply aspects on your opponent as your defense - if you're willing to lie.
My doubt comes from the fact that the description says that you can use Deceit to attack (Cat and Mouse)
instead of defending with it (False Face Forward). It also says that this is an option for when someone else initiates the conflict, which means you have already been attacked (presumably). So, as I see it, it's either like the Weapons stunt Riposte (you defend and if successful turn that same defense into an attack), or it means something like... you
have to defend with a skill different from Deceit if you want the option to later on attack with Cat and Mouse on your turn. I think the former makes more sense narratively (why wouldn't you be able to both put your false face forward
and lie to attack?), but either way, it's not explained very well, imo.
