Eg, a notification like "Alice is online" in some languages requires knowing Alice's gender. Which may be something that's not even stored anywhere in the system. There's probably some language out there that requires some other piece of personal info for a correct translation.
To make things tricky, try having a multitude of items that you refer to: "You're holding a dagger". Now you need to have a serious discussion with your translators, because this is going to get all kinds of tricky, as the maker of Obra Dinn discovered: https://www.youtube.com/watch?v=OMi6xgdSbMA
And to make things extra-tricky, allow users to create content. "Alice gave you a banana", where "banana" is a custom object Alice made herself.
Most translation efforts seem to give up at this point and resort to something stilted like "Alice: online"