MTL with some editing is probably enough even without gpt for the lowest end.

Then you can get some hobbyist or Chinese person for next tier.

But you will probably always want professional for legal and contractual work, translating international treaties and interpretation at high level. We might get somewhere close, but I think for situations like UN you will always want live person at least some of the time.

And probably for literary translation as well... Although I'm not so sure in the long term, in light of the progression of the GPTs.