I do not currently have a video with subtitles but I do have this video I edited on my profile page. I assure you, adding subtitles is very simple. A 4 minute video I can complete fairly quickly.
Relevant Skills and Experience
Subtitles can be SRT. files (a sidecar file) that you load up. I can merge them into the video, as well, if you prefer. (I can add subs that you can shut off and on or burned in; your preference)
Proposed Milestones
$14 USD - Add Subtitles
What file type would you like the video to be? (.mp4, .mkv, etc.)