Hello,
Eco doesn't really contain any voice lines that would need to be translated - did you maybe refer to something else that was lost in translation?

If I didn't bring Chinese, can I bring Chinese with me in the next update?

I'm not sure what you are trying to say - we do have a Chinese Simplified translation for Eco and Eco doesn't contain any notable voice lines, hence there is nothing to be translated in regard to audio.

You mentioned simplified Chinese, so I would like to ask you where the simplified Chinese is, is it in the game body or on other websites

You can set the language in the ESC menu, it's the first setting on the first tab.

So here's the problem, what about creating a new world where 90% of the interface is in English, and the interface is not in the center of the screen but to the right

Can you post a screenshot?
Is the server you play on set to chinese as well (language for server and client are separated, if server is in english, everything the server provides will also be in english)?

Note that all translations are WIP and community-made, they are never fully complete and depend on that translation progress.

I have a picture but don't know how to upload it

Mine is the client

https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=3370019351

Yes, that is normal - these strings were only recently added to the game, the translations are community-made, it takes a while for them to be updated. We do not offer any translations ourselves, any translation with 80% or more progress is considered supported.

So what's the problem with this interface that I want to look at

There is no translation for the new strings yet.