Refined from version 3.2. comes with additional support for switching language on your portals. Read more about it here: Site Languages.
Customer-facing and non admin areas
We're supporting the 23 languages Jira offers out of the box (see below) for our customer facing properties. In addition to these we're currently also offering Vietnamese (vi_VN) as well as Portuguese (pt_PT). In order to fill the gaps on Atlassian properties for these languages a Jira Language pack might need to be installed, see guide here.
For Jira Service Desk and the customer facing parts we offer to build a translation JAR based on translations provided by you. Read more about Translations for Refined for JSD.