Maybe it should be an independent model in charge only of converting your question to American English and back, instead of trying to make a single model speak all languages
I don't think this is a good idea. A good model if we are really aiming at anything that resembles AGI (or even a good LLM like GPT4) is a model that have world knowledge. The world is not just English.
There’s a lot of world knowledge that is just not present in an American English corpus. For example knowledge of world cuisine & culture. There’s precious few good English sources on Sichuan cooking.
And this is most noticiable if you ask anything that is not in English-American-ish.