how silly does futo sound in japanese? most translations make her talk in really overblown faux-shakespearean english, which is kind of a pet peeve of mine because it turns her into a joke character - but I don't know to what extent this is supported by the original. is she using old-fashioned language correctly, or is it supposed to sound funny? and how old-fashioned is her speech compared to how she's translated? like is it the equivalent of 1500s english or is it older/newer? thankyou!
Futo's speech is way more exaggerated in many English translations than in Japanese, yeah. Personally I tend to vary it depending on the tone of the story, how extreme the author is doing it (in the case of doujins) and the feng shui in the room, but I honestly kinda struggle with the issue too.
Futo basically speaks "period drama Japanese". Doesn't really even matter which period, everything pre-Meiji is mostly interchangeable as far as the trope is concerned – it's not really supposed to be an accurate representation of old Japanese, which would be much harder to understand. It's actually a lot less extreme than, say, Mamizou's manner of speech, but intended to convey "old-timey" rather than "old-timer". Where Mamizou speaks in the stereotypical manner of a country grandpa (more so than a grandma, really), Futo speaks like a character who's literally from the past. Or maybe a yakuza or hammy cartoon character. Not even an especially fancy court official, and also not a samurai (which its own trope de gozaru).
Problem is, in Japanese, verbal tics like that are easily conveyed by things like choice of pronouns and sentence endings. Those are things you can consistently stick in almost every sentence without really altering them or even being all that grating (the tics here being more like "zo" than "kupo", "nyan" or even "desu"). In terms of actual vocabulary or verbose loquaciousness, Futo doesn't really stand out from anyone else.
This is different in English, where to convey things like "medieval speech" we don't have easy shortcuts like "the old-timey sentence ending" and are instead dependent on vocabulary, grammar and wording choices to turn the whole sentence "Shakespearean" (which of course is anachronistic too) in pretty ridiculous ways. The Ten Desires translation manages to turn very basic and short lines into "Thou who hast prais'd my resurrection: Speak anon, and name thyself." Of course, the small ways that the pronouns, particles and overall phrasing convey tone in Japanese is hard to explain directly, just like it's hard to translate English tone to Japanese. English sentences also tend to be longer in general than Japanese ones, but that difference is just widened even further.
In a sense, you could say that English has no choice but to go to those much greater and more annoying lengths to make Futo's way of speech "as obvious" as it is in Japanese. But while Futo's whole thing is also silly enough in Japanese for the fandom there to acknowledge and make jokes about it, I do sometimes feel like it's gotten out of hand and become kinda self-sustaining on the English end, rather than actually based on the original text anymore.
In theory, my preferred way of writing Futo is to make her sound slightly stilted in some less grating ways, like avoiding contractions and very obviously modern words, throwing in the occasional archaic one if I feel like it fits, and kinda chewing the scenery a bit. Maybe even the thee/thou stuff, especially if the work is more comedic. But the execution varies on my part, and sometimes I just sacrifice the whole idea at the altar of legibility.