Our IDX is currently only available in English- however, if you're looking to offer alternative languages, we have a suggestion.
You can use a translation plugin to change the language directly on your site. It is important to note, however, that a lot of the IDX may not be translated.
Be careful with the URLs. For example, if you default to Spanish and someone changes the language to english, it usually adds "/en/" to the URL. This URL change would break the IDX search but there are ways around that. Be sure to not have either of the sub-directory or sub-domain items selected in your plugin of choice. Settings may vary depending on your plugin.