I believe this may not be possible, as you’d have to modify at vendor’s (Microsoft/Google) level. Unless, translated content is subject to the word replacement feature, then you can use that.
Here’s a feature request though:
- Autotranslate the first post to English in case it’s written in different language.
- Have a button to translate the entire thread at once.
- Have autotranslate feature enabled for entire forum on user-level. Meaning, if user selects in their profile that they only speak e.g. Romanian, then translate all content to Romanian. If they select they speak multiple languages, posts would be translated only if not in these languages.