Hi, and thank you for your interest!
PDFCreator is being translated using Weblate, a web tool designed to ease translating for both developers and translators.
Translation project for PDFCreator into Basque currently contains 775 strings for translation and is 17.7% complete.
If you would like to contribute to translation of PDFCreator, you need to register on this server.
Once you have activated your account just proceed to the translation section.