Approximately 98 songs.
: Each album can be purchased individually for permanent offline use. Free & Legal Streaming (Offline Support) One Direction All Songs Download Zip File
A: No. Sony Music has never released an official .zip file of the entire discography. Any site claiming to offer an "official" zip is lying. Approximately 98 songs
If you don't want to buy albums individually, premium subscriptions on these platforms let you "download" the entire catalog for offline listening within their respective apps. One Direction All Songs Download Zip File