No talent currently attached, but HBO is moving forward with a Dunk and Egg series. https://variety.com/2021/tv/news/game-of-thrones-tales-of-dunk-and-egg-series-hbo-1234889520/
If they do this right it could be amazing, like really really good. I think this is some of GRRM's best writing, I was very sad when it ended. Felt way too short. I wonder if they would take the series all the way thru the Tragedy of Summerhall, if the established material went well. They could definitely end it that way, with some type of look into the future.