Round 1: Even an untrained Sidious was naturally repelling telepathy from a far more advanced and powerful Sith Lord than Zannah in Plagueis. With decades of training and mastery, Sidious would absolutely shrug off Zannah's spell.
Round 2: Sidious stomps. Far greater reserves/raw power, far greater physicals, significantly greater skill, and far more brutal than anyone Zannah has ever fought (and yes, that includes Bane).
Yeah, Sidious laughs it off. He's immeasurably more powerful than anybody Zannah's attempted her Sorcery on, especially with regards to mental resiliency. He's also actually practiced/is aware of/presumably knows how to defend against Sorcery, unlike Zannah's victims. He'd be immune to her most powerful, charged-up spells whilst sleeping.
And round 2 is a stomp of epic proportions, of course.