Youtube Subtitles automatic translation (using Google/Bing translators)

Feature for youtube automatic subtitle translation when download a video, using Google translator and/or Bing translator or similar translation websites.
A feature Really useful when there are only English subtitles and we want translation in other languages in a fast and simple way (automatic and transparent to user, with no need time spending to use external tools), the user simply select the target language and 4k video downloader make all itself (download srt > translate > mux subtitles to video file)