You can set language preferences in Talend Studio. To do so:
From the menu bar, click Window > Preferences to open the [Preferences] dialog box.
Expand the Talend node and click Internationalization to display the relevant view.
From the Local Language list, select the language you want to use for the graphical interface of Talend Studio.
Click Apply and then OK to validate your change and close the [Preferences] dialog box.
Restart the Studio to display the graphical interface in the selected language.