Adding OpenAI's ChatGPT API as one of the translate options could be useful.

Especially if there was a 'context' field which could be passed to the API.

It would allow you to add context telling it that you're writing e.g button microcopy, which could then influence how it translates a word (e.g. whether 'Cancel' should be translated into the imperative voice or the infinitive).

You could also add voice and tone instructions asking it to be playful, or avoid the second person informal and so on.