Though it has been previously said to be unlikely for an ATL unified Indian Empire to conquer let alone retain Nanzhao / Yunnan, what is intriguing about such an idea would be the easternmost borders being south of the Yangtze River and west of the Pearl River in part or most of Yunnan (53 on map below).
OTOH would it have been more feasible for the easternmost border of this ATL unified Indian Empire being west of the Lancang portion of the Mekong River that only includes a small part of Nanzhao/Yunnan?
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