This is how Mochi[0] works. It exports a .EDN file that describes the cards, decks and review history. There are a few libraries out there that work with the format[2] but no one has adopted the format in their own apps AFAIK. Anki also has an export format but it's not documented.
[0] https://mochi.cards/ [1] https://mochi.cards/faq.html#how-can-i-create-my-own-mochi-f... [2] https://github.com/knubie/subs2srs