How is her speech translated by O-T? Specifics now, I don't want some wise guy saying "correctly".
You can download the script from O-T's site

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Like I said she speaks in formal english. For example, in the last episode,
1. "Hanashite", instead of the commonly "Let go (of me)!" became "Release me!".
2. There are almost no contractions, so "Konna koto ni..." was translated into "This cannot be..."
3. Phrases that convey extra thoughts are added, like what is common in what is commonly regarded as gentleman's English, such as "I believe it's time to go grocery shopping" and "I intend to stay with my world until the end." are used to translate "Watakushi wa _____ kaidashi ni" and "Watakushi wa saigo made koko ni imasu, kono hoshi ni." "I would like to join your crew. I wish to become a pirate!" was the one used for "Watakushi wa nakama shite kudasai. Kaizoku ni naritaindesu!"
4. Also, like I said, O-T makes her call Don "Mr. Don" to express the difference between how she calls Don "Don-san" and the rest of the team uses just "Don" without using the honorifics.
The direct translations would've been much shorter, but they add in things to give the words the same flavor it would have in English as it does in Japanese without giving the words a different meaning.