All the features you need:
Xoctave is multilingual and any language can be added easily. Xoctave is based on Free Pascal, Lazarus, LCL programming language and integrated development environments (IDEs). Xoctave connects to GNU Octave via pipes and does not possess GNU Octave installed in the initial installation package. GNU Octave should be downloaded and installed separately.
The support of multiple languages by Xoctave is considered through internationalization ("i18n"). All GUI components, warnings and errors can be viewed the target language. GNU Octave related commands and text such as warnings and error strings cannot be translated unless you compile GNU Octave. All GUI strings, captions, and messages can be converted to a different language using PO files. Please translate the provided PO file and compile. The language then can be selected using preferences window.
The language is a user preference. To change the language of the Xoctave, click on the menu: File > Preferences > languages page.