This blog post is going to show you how to translate Odoo module to a different language. I have published a tutorial on how to translate Odoo website some time ago and due to its popularity, I have decided to write a tutorial on how to translate Odoo modules. It is because not everything can be translated from the front-end translator, especially third-party modules. This may result in a website with mixed languages as shown on-screen below.
Export original language file
Go to settings and activate the developer mode, then select translations/export translation.
Here you can choose the application that you want to translate and file format.
Translate file using your text editor
Once you have your language file simply place it in the i18n folder in your module folder (create one if necessary).
Now translate phrase by phrase.
Apply translation
You can upload and update the translated module on the server and this should do the trick.
In Settings (activate the developer mode first) you can also upload translation manually and update for the chosen language.
Check if everything is ok
After loading the translation test if everything is displayed properly before you deploy it on the live server.