Is there a way to directly convert .mp3 audio files to .mts format.
Converting MP3 Audio Files directly to AVCHD Videos (.mp3 to .mts conversion) is possible and quite straightforward. It relates to users attempting to encode MP3 audio to MTS video.
Try using a media editing software or (online) conversion tool, such as MediaCoder or Freemake Video Converter, which should allow users to import MP3 audio and export it in MTS format.