Access uses a library of text and messages for each language. You can download a language option file from Microsoft and can even manually make a given database file prefer the new language as a default. There are YouTube videos on that process.
The catch is that to have that language change (which is done through the File >> Options path) to take effect, you must close and restart Access. That tells me that the language change acts based on dynamic links built into a DLL file, which includes getting mapped into the MSACCESS.EXE program image. If Access doesn't have this kind of dynamic language feature built-in then you can't do what you wanted unless you somehow simulate it yourself.
More precisely, while it may be possible to change the language selection, you would not be able to keep Access open AND change the language in a way that it immediately takes effect.
If another of my colleagues knows a way to do this, I would defer to their knowledge, but I don't see an easy way because of the need to select what I believe to be a different language's library file via actions that normally only occur during image initialization.