wpl to m3u conversion is usually to case of conversion or export between two different media player playlist files, namely standard Windows Media Player playlists (.wpl) and MP3 playlists (.m3u). The easiest way to convert WPL playlists to a M3U ones would be to import the first to a media player that supports both and simply save it as .m3u file afterwards.
Open WPL file Open M3U fileAdvanced playlist creator and manager