Theory: Location of Emerald Woods and Gold Links and Crystal Beach

Abstract
Emerald Woods, Gold Links and Crystal Beach, golf courses from Mario Sports Superstar, are all located in the Diamond City Region (WarioWare games + other implied appearances).

Arguments

 * Argument 1: Diamond City has suburbs around it, as shown by one of Mona's cutscenes, where the young redheaded woman is going through them to reach the city.


 * Argument 2: The landscape of Diamond City is between the mountains and the coast, respectively just like Gold Links and Crystal Beach. Forests are also featured in the Diamond City region, like the Agate Forest or the ones around Peridot Campgrounds.


 * Argument 3: Terracotta orange roof houses are featured both in Crystal Beach & Gold Links and in the suburbs. Gold Links has many other terracotta houses scattered in its background.


 * Argument 4: Crystal Beach, Gold Links and Emerald Woods follow the gem naming convention that the locations of the Diamond City region follow.