This is according to the official Nintendo Eshop of 2K, which can be seen by players who play on Nintendo Switch:

"The Babylon Pack introduces Hammurabi as the leader of Babylon. The Babylon civilization excels at Science, as well as Government and Infrastructure. Also included is the new Heroes and Legend Game Mode, two unique improvements (the Mahavihara and the Trading Dome), six new City-states, and 24 new Great People."

The pack will be released on November 19th, 2020.

https://forums.civfanatics.com/threads/civilization-vi-possible-new-civilizations-thread.657838/page-440#post-15945374

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