comments:
EpicEmpiresRPG posted on r/osr2w
Fabled Lands is probably the closest to what you're looking for. Multiple large books in the choose your own adventure style, but they're played largely as a sandbox. You can literally move from one book to another and back again.https://www.drivethrurpg.com/en/product/478957/fabled-lands-1-the-war-torn-kingdomhttps://www.amazon.com/dp/B09N2PRYLS?binding=paperback