I’ve just installed Lingua on a new site. Within the extra where the languages are specified, these two languages are not showing the proper characters. On my other site, with the same version of lingua and modx they display correctly.
On the front-end, the Chinese symbols display as question marks–on three different browsers.
I checked the system settings, both sites have character encoding set to UTF-8. The database character set is utf8 as reported in the Modx reports–system info.
I suspect that that’s your issue. The fix is usually not trivial. There’s more info here.
Whether it works depends on the actual content of those fields (i.e., is it utf8 data in a latin1 table, or is it latin1 data in a latin one table being messed up by the site’s utf8 setting).