Google translate was always bad, at least from and into Russian, German and English. I've used it on and off from 2007 - 2020 just to see how it improved. It didn't. Don't benchmark against something that makes a sophomore sigh.
Get 4 years of multicultural students @ universities that focus on language studies. Feed LLM's the translation exercises. Record the sessions with the teachers and professors. Let the students revise. Repeat. Let LLM's learn the nuances and perspectives by following students through their evolution. Build LLMs that want to learn from students and not the other way around. Let the LLMs discuss it all with each other at human speeds and let the crowd moderate the conversations.