I do think it's very internally consistent, and that it feels pretty authentic. My issue is that, if you compare it to the actual literature of the period, it's over-cautious and flat. I'm not saying the adapter needs to be Shakespeare or Webster, but if you're going to write in an unusual form of English, I think you need enough intimacy with it to go further than just accuracy. You have to be able to write in it - if you can't, what you're doing is demanding more of the readers than you're able to give.*

Which I think is both bad writing and bad strategy, but to an extent I guess it's par for the course in translated manga. We're accustomed to wading through painfully awkward translations for the reward of (presumed) cultural authenticity.

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* I should add that my knowledge of Elizabethan/Jacobean language is mostly from a single college class where we analyzed a bunch of stuff to see how gay it was (pretty gay, some of it!), and from regular re-reads of The Duchess of Malfi. So my opinion's weight must be scaled accordingly.