Personally, I've been setting things up to have it translate a series of light novels from Japanese to English. Experiments through the chat interface show it's working; now I just need API access, to fully automate it.
This is not talked much right now but language learning will become a hobby at this point between the increasing quality of speech recognition, translation and speech synthesis.
Sure right now you can't use a product which works very well with those bricks together (I've seen some but it's still unconvincing) but in 5 years maximum this is a solved problem.
I'm even expecting the global English level to peak and then decrease because of that in the next 20 years. Learning foreign languages is very hard and less people would continue it just as a hobby if they have some software doing it for them.
If you talk with a stranger it is usually something along the lines of needing to find a place or person, wanting to eat, drink or sleep. As people are intelligent, most will understand just from the situation what is the likely mission or needs of the stranger. The other purpose of talking with another person is to socialize and establish acquaintance or friendship. An AI will not help you with establishing a human connection. It is all in the tone of voice, the body language, the eyes, the smile.
If you want to communicate anything complicated or different than the above, a written translation is preferable. In almost all situations, using an AI voice translation will be met by the reaction "Why is this creepy man bothering me?"
There's some prior work: https://www.scientificamerican.com/article/how-scientists-ar...
That really depends on the language. It's still kinda awkward at Hungarian. Personally, I think DeepL is still way better at translation.