I've found the freeware MP3TAG https://www.mp3tag.de/en/ very useful for adding tags (including ISRC) to audio files (MP3, WAV, FLAC, etc.). FYI.
MP3TAG can only add ISRC in ID3v2 tag. It can be embedded in both MP3 and WAV files, but For WAV files, there is also a special standard for embedding ISRC, that MP3TAG does not supports. (in an 'axml' chunk)
Two apps that supports adding it are:
1. ISRC Editor by Sonoris Software
2. MetadataTouch by Digital Confidence
Can I embed an ISRC code into a wav or mp3 in CbB?
in Cakewalk by BandLab
Posted
MP3TAG can only add ISRC in ID3v2 tag. It can be embedded in both MP3 and WAV files, but For WAV files, there is also a special standard for embedding ISRC, that MP3TAG does not supports. (in an 'axml' chunk)
Two apps that supports adding it are:
1. ISRC Editor by Sonoris Software
2. MetadataTouch by Digital Confidence