New Pokemon are coming to Pokemon Go globally as part of the upcoming Pokemon Go summer tour 2018.
The Alolan forms of Diglett and Geodude will appear globally for the first time in Pokemon Go beginning 14th and 15th July (the weekend Pokemon Go Fest 2018 takes place in Chicago).
Meanwhile, Trapinch, Feebas and other Pokemon featured in the habitats of Pokemon Go Fest will appear more frequently all over the world during that weekend. The Cheering Pokemon, Plusle and Minun, will also appear more frequently worldwide (catching Plusle and Minun gets you bonus Stardust and a chance at finding their shiny versions).
Source: Eurogamer Alolan Diglett and Geodude coming to Pokemon Go