Mexico City
The game has transcended the borders of the country already, as Toronto has proven more than capable of not only supporting the Raptors but providing one of the most dedicated fan bases in the game.
Let’s not get crazy funky, as crossing the Atlantic Ocean and significantly changing time zones has already held the NFL back. It will likely do the same for the NBA.
Mexico City has already hosted plenty of basketball games, including two more this year at Arena Ciudad de Mexico. Basketball has plenty of following in South and Central America, so putting a team south of the US border makes sense.
Also, it is not too far from the states to make travel time a concern. It’s only a handful of hours to get to any city where a team currently plays.
The NBA would be the first of the major professional sports leagues to have a franchise in Mexico, but it is a sensible landing spot.