The Mother franchise, known as EarthBound in the West, has had an extremely complicated history when it comes to international releases. The final game in the series, Mother 3, has still never seen an official release outside of Japan since its debut in 2006. Fans have requested this so often and for so long that Nintendo even joked about it in an E3 presentation. Unfortunately, it increasingly seems like the eager fans will never get their wish fulfilled.
The original Mother was planned for release on the NES in the United States decades ago, and Nintendo even made an official localization and printed off a few copies. However, by the time Nintendo had reached that point the SNES was already on store shelves, and it seemed like a poor investment to mass produce and release the quirky RPG. Mother 2 was released in the West as EarthBound, but it sold poorly in its initial run. Mother 3 released on the Game Boy Advance in Japan in 2006. Because of this, it found itself in a similar situation as the original game, as the Game Boy Advance had already been replaced by the Nintendo DS. Nintendo opted not to release it the West.
Years later, Nintendo would finally re-release both Mother (renamed EarthBound Beginnings) and EarthBound on the Wii U eShop, and many fans wondered if Mother 3 would soon follow. This seemed like it would be the case in 2016, as numerous tipsters hinted that it was coming, but eventually everything went silent. Years later, Nintendo still hasn't given any indication that it's coming.
According to Game Informer's Imran Khan, the rumors from years back weren't exactly false. Nintendo was planning on an official localization for Mother 3, and they were "full steam ahead" on the project. However, after spending some time evaluating the game's content, they determined that a re-release would likely cause controversy. Khan believes the project is now a "dead end" based on what he's heard.
Source: Imran Khan