If I have Punisher: Jury and I attack, may I respond with plot twists effects and then equip him with a Personal Force Field or do I have to equip him then and there?

Punisher, Jury has a triggered power, and so when he attacks, a triggered effect is placed on the chain; you can still add to the chain before the resolution of this triggered effect. And Punisher is an attacker at this point, so you could still target him with plot twists which require an attacker---the Savage Beatdown genre, notably.

Of course, your opponent can also add to the chain before the resolution of the triggered effect, so watch out for an opponent who likes to combo attack pumps with Overload.

Cool thanks.