Converting .pls files to .mp4 format.
Converting Multimedia Playlist Files directly to MPEG-4 Videos (.pls to .mp4 conversion) is not possible, since PLS files are neither audio nor video files.
If you want to convert media files, referenced by your PLS playlist, to other formats, you must first locate/download those files. You can then easily convert those files using most available media editing programs or (online) conversion tools.
In a word, direct pls to mp4 conversion is not possible.
So don't expect any so-called pls to mp4 converter or pls to mp4 free online conversion tool available.
The database currently does not contain any pls software converter.