There are two more animated series set in the world of Game of Thrones in development for HBO Max (now three in total), and one of them is expected to focus on a previously unexplored region of Westeros.
THR reports that one of these potential shows will be set in The Golden Empire of Yi Ti in Essos. This location was inspired by Imperial China, and only ever mentioned in passing in George R.R. Martin's A Song of Ice and Fire saga. No details on the animated spin-off are known at this time.
In related news, HBO has decided not to move forward with one of its live-action prequel shows. Tentatively titled Flea Bottom, the project would have been set in the infamous King’s Landing slum, but sources report that this "was always the most nascent of the ideas that were made public and was never officially confirmed by HBO."
As far as we know, 10,000 Ships, which has screenwriter Amanda Segel on board, and Bruno Heller's 9 Voyages (Sea Snake) are still on track along with Tales of Dunk and Egg.
As of right now, the only Game of Thrones spinoff that's guaranteed to air is House of The Dragon, which has been given an official 2022 premiere date.