To ask how Canon!Akane would react seems to me to be asking how Takahashi-sensei would write the scene, if she were to have done so. In which case it could turn out many different ways, depending on why she wrote the scene into whatever story arc contained it. Although I think it would most likely be played for comedy.
So I can easily see Ranma and Ryoga running for the hills, hands held behind their heads protectively, while a veritable storm of household items are thrown at them.
Or I can see Ranma, having let the truth slip, teasing Akane while dodging her attempts at retribution. Until she finds something to distract him and punts him into the sky.
Or I can see Ryoga accidentally transform, a look at Akane's face while a thunderstorm forms above her head, then a cutaway to a scene of Ryoga in a hospital bed, bandaged from head to toe.
Or I can see (ignoring all previous evidence to the contrary) a revelation that every other character knew about his curse. Akane slumps to her knees, not knowing how to react, when the generally oblivious Kasumi asks, "You mean you didn't know?"
Or I can see Akari showing up just at the moment it is revealed and discovering, from Akane's reaction, what her "boyfriend" Ryoga has been doing. Just as Akane is about to wreak vengeance, Akari beats her to the punch, chasing Ryoga around, hitting him over the head, calling on her sumo pig to clobber him, etc., etc. All while Akane looks on, befuddled.
The one thing I'm sure of is that Takahashi would write it so that Akane and Ranma's relationship would remain essentially unchanged, perhaps after some initial reaction, and that there would be no permanent animosity toward Ryoga. Although I could see Akane's attitude toward Ryoga being changed for comedic effect, with her misinterpreting future events involving Ryoga. (Ryoga gets lost, wanders into the girls' locker room, and Akane chases the little pig, calling it a pervert, while refusing to explain her bizarre behavior to the other girls.) Or maybe she'd forgive and forget after it was over with. Takahashi did like to restore the status quo.