https://www.winxdvd.com/video-transcoder/add-subtitles-with-mkvtoolnix.htm
[Tutorial] How to Add Subtitles with MKVToolNix GUI
Here we'll walk you through the steps to add subtitles with MKVToolNix. Moreover, we'll answer FAQs about how to use MKVToolNix to hardcode, remove, extract,...
how to addtutorialsubtitlesmkvtoolnixgui