The action-movie parts don't reach 's prose style, but get stiff trying. The interpolations do patch something that makes Austen's novels hard to read as realistic novels now; 'zombie-fighting skill' is used to replace 'good birth' as a social essential. It's not as good a replacement as 'high school cool' is, because it doesn't have the network effects or the effects of charisma, but at least the sense of importance is right.
Nor was I convinced by Japan as a contemporaneous source of mysterious fighting skills. Of course, if one is imagining ninjas, they would have existed then, but I don't think England of the day would have been thinking of ninjas. Studying with the Old Man of the Mountain would seem more likely to me, or learning from a mysterious temple in India; something inherited from the Gothics or .
I didn't finish the book, so; not a fair review.
Find in a Library: Pride and Prejudice and Zombies
So wrote clew in SF&F.