@lukasz NetSuite provides translation strings for the user interface and for printed transaction forms. The Multi-Language feature also supports the use of several additional languages for Web site translations, but these languages must be defined in company preferences and translation strings must be provided.
Website elements can be translated to display in each visitor's language. These elements include Web site items,
, tabs, categories, email forms, text, and images, and formatted Web site text.
Also the list of supported languages for website translations is :
The above is taken from HELP section