Hello,
Well, this is indeed a really tricky issue, as the translation is done using AI on Google Translate’s part. Because of this, telling it that it should translate words always in the same way is not possible.
Also, replacing words with Regex is not a good idea, as the text will be sent Google Translator with some words already translated (the ones replaced by Regex), which will confuse the AI translator and it will think that it should translate also the already translated words.
Maybe try switching to AI translation using the Aiomatic plugin and tell the AI Editor the exact words which it should replace with what version of translations. This should be a solution which might be able to help solve this issue.
Regards,
Szabi – CodeRevolution