Converting .xspf files to .mp4 format.
Converting XML Shareable Playlist Files directly to MPEG-4 Videos (.xspf to .mp4 conversion) is not possible, since XSPF files are neither audio nor video files.
If you want to convert media files, referenced by your XSPF 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 xspf to mp4 conversion is not possible.
So don't expect any so-called xspf to mp4 converter or xspf to mp4 free online conversion tool available.
The database currently does not contain any xspf software converter.