Is there any video player app which allow to drag the subtitle to a news position? Ideally it may allow to add more than one subtitle to screen.
I use avidemux.
Although if/how it works depends on what kind of video and subtitle files you have.
----- UPDATE -----
My answer is based on avidemux 2.5.3. The now current version 2.6.8 changed how subtitles are handled, and the ability to move subtitles seems to be gone. You may wish to check 2.5.3 for this kind of function, especially if you are using SRT subtitle files.