Yes it does.
In fact, there’s complete module designed specifically for subtitle management to help you get organized.
And, since all four players we’re using, as most modern web players, support WebVTT subtitle format, if you upload .srt subtitle to XtremeStream, it will get converted in .vtt format so you don’t have to use any other third party service.
You can also add as many different subtitles for each video as you like or need so you can have one video with many different subtitle languages.
Only difference is if you use PlyrES, which supports only one subtitle per video.