Alvind

Enabling the ability to set your own WordPress REST API Prefix (/wp-json).
<h4>Contribute to Custom REST API Prefix</h4>
Development for this plugin happens in a public GitHub repository. If you have a suggestion, bug report, patch, or pull request, please feel free to <a href="https://github.com/alvindcaesar/custom-rest-api-prefix" rel="nofollow ugc">contribute here</a>.

Custom REST API Prefix

A simple plugin to customize the default WordPress REST API prefix.

Ryuhei Yokokawa

Plugin will allow you to fetch the WP-API (WP-JSON-API) call with a “lang” variable. It will retrieve the right content from WPML/WP.
This only works with WPML and WP-API installed. I tested only with the latest version as of now: 
* WPML 3.1.9.6 
* WP REST API 1.2.1

WPML to WP API

Allows you to request a language with your WP-API and WPML site.

Custom REST API Prefix vs WPML to WP API