Most of Madara's knowledge comes from the stone tablet which Sasuke already must've read. Not to mention Sasuke has much better access to Otsutsuki knowledge through Kaguya's dimensions. I doubt Madara would add anything significant on top of that.Madara can teach Sasuke, Sarada and the Shins in Kabuto orphanage. Madara knows many secrets about the Sharingan, MS, EMS and Rinnengan which most ninja has no idea.
I wonder if Madara could see and hear anything when Kaguya was in control of Madara body.