Hi, and thank you for your interest!
Exaile is being translated using Weblate, a web tool designed to ease translating for both developers and translators.
Translation project for Exaile into English (Australia) currently contains 1025 strings for translation and is 79.1% complete.
If you would like to contribute to translation of Exaile, you need to register on this server.
Once you have activated your account just proceed to the translation section.