How about zipping pure text or Markdown files, splitting them into QR-code sized chunks (1.5-3KB), converting them to QR-codes and printing all those on a singl

How about zipping pure text or Markdown files, splitting them into QR-code sized chunks (1.5-3KB), converting them to QR-codes and printing all those on a single paper sheet? You can choose their sizes depending on how redundant you want them to be. And restoring them is just doing the same in reverse. I believe you can fit pretty big texts this way without delving into a rabbit-hole of some obscure formats. Python app code for decoding that, using existing modules, should fit on a single A4 sheet too without any encoding.