Comatose
Tough Claws
Shield Dust
As I said before, CAP23 is going to appreciate a defensive ability first and then once stats get sorted out, the secondary ability will be much more favorable towards an offensive one if the stats were to suffer as Lucario said.
Comatose is my favorite simply because we can have it as a defensive ability that is used offensively in that CAP23 can trap the targets it wants to dismantle all while avoiding any type of status purely based on its offensive presence (which is really neat when you think about it). That being said, I wouldn't mind to see Tough Claws win, especially over Shield Dust, but I just feel we need to have the defensive option before we think about beefing its offensive option because you can also hinder stats, and potentially its movepool, by giving it Tough Claws before a defensive ability like Comatose, which helps aid in threatening the Pokémon we want CAP23 to target.