Differences in verb-subject-object word order will always add latency. If you want to translate from German, with the verb at the end, to Welsh, where the verb goes at the start, you'll have to wait for the complete sentence before you can begin.
That said, I suspect that real-time language translation is always going to be somewhat imperfect due to its nature. Non-real-time translation of literature is still a subjective art form even at the very high-end of human expertise.
It's all a trade off.
Either way it's extremely exciting that we get to even discuss this stuff as real possiblities.
This may be apocryphal but I’ve heard that in formal settings (e.g. UN) they won’t translate it and will instead give instruction on when to laugh.