Rajat

This Plugin Create a options which can provide ability to disable all or particular routes for json api.This plugin 
help to restrict the use of public credentials of website.This will protect the data such as users details of wordpress 
etc

Restrict Json Rest Api

Plugin to restrict json rest api, which you want to restrict to use from outside

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.

Restrict Json Rest Api vs WPML to WP API