There are no irreversible mistakes when putting files on an SD card.
Just put a current, standard Hekate release on the card (after understanding how Switch homebrew works, of course) and be done with it.
Make a backup of the existing files just in case, that is enough. But I bet 99% of your problems are fixed by just replacing whatever chinese Hekate is on there with a current English release.
I do not really know how language in homebrew works. If it is really affected by the Switch system settings. Some might be, others won't. In the case of hekate I bet it's the files themselves and if you just update Hekate to latest release on github, it's English. If there are any doubts afterwards, just change system language to English and see what happens. This is by no means any language problem, it's a problem of the settings and/or the files.