Ok....so I *think* this worked.
My old steam installation was here:
/home/UltimaPapazov/.steam/debian-installation/steamapps/common/Lust Academy/
I created
/home/UltimaPapazov/.steam/debian-installation/steamapps/common/Lust Academy 2/ <- just guessed what this folder should be called.
Extracted the itch.io Season 2 files to that folder. Ran the Season 1 install via Steam, performed the Load screen export. "New notice: success" Closed out. Opened Season 2 "/home/UltimaPapazov/.steam/debian-installation/steamapps/common/Lust\ Academy\ 2/Lust-Academy-2.sh" via command line. New Game -> import was there.
:: phew ::
Viewing post in Lust Academy Season 2 (NSFW 18+ Erotic) comments
Already playing it. What a great game!
And quite happy to pay for Season 1 twice to support the development.
Some thoughts: The way other visual novels like 'College Bound' handle unsuccessful import is just run the player through all the consequential choices they've made. Ask the player about their choices in a very quick format. And it's even better because if I didn't like my choices my first run through I can change 'em.
OR just provide more information as to what the Export function is doing - I'm sure that "New note: success" was making some file. I could move the file it was generating if I knew where it was. I don't mind jumping through a few hoops and solving a mystery when I have the time...but I paid $10.75 on Steam and then just now $20.60 on itch. Please - next time just tell me what the export is doing.