The overwhelming majority of Nintendo games are crafted with both Western and Eastern audiences in mind. However, the occasional oddball crops up that's just too nestled in its Japanese roots to justify the complicated localization process necessary for a US release.
Whether its a game that features an untranslatable emphasis on Eastern culture, or a launch title tied to a system that never made it out of Japan, there's a lot of Nintendo releases that North America is missing out on. Some of these games are fascinating, and it's a real shame the US audience was never able to experience them first hand. That being said, there are also a handful of incredibly strange games that should probably never be allowed out of Japan.
The Amazing Spider-Man: Lethal Foes is a mystery. How on earth could a Spider-Man game not reach the West, the home of the character and his biggest market? The world may never know. All that is known is that the US missed out on an awesome 2D beat-'em-up featuring everyone's favorite wall-crawler and an impressive lineup of villains from his rogues gallery, including Venom, Green Goblin, and Carnage.
Excitebike, a 2D motorcycle racing game, managed to secure a Mario crossover title that never reached North America. The game released exclusively for the Super Famicom, the Japanese SNES, through a device called the Broadcast Satellaview. The game had to be downloaded through the Satellaview, and was released a year after the N64 came out. It would have been counterintuitive to create an outdated cartridge for Western audiences, and it was impractical to implement a new online service for a single localization.
A truly innovative game in its own right, Mario Artist for the 64DD (64DiskDrive) had the potential to revolutionize its industry. The game planned to allow players to paint, compose music, render 3D shapes, and create their own 3D animations. Nintendo wanted players to use these tools to create their own minigames, and to modify content within other 64DD games. It could've invented a console modding scene a decade before the concept even came into existence. However, the 64DD was a commercial failure in Japan, and the game never saw the light of day in any other region.
The Mother series, a set of RPGs known as EarthBound in Western territories, has always had its fair share of troubles when it comes to localization. Only Mother 2 reached Western shores within a reasonable amount of time from its Eastern debut, and Mother 1 took 25 years to become localized on the Wii U's e-shop. Mother 3, however, hasn't arrived as of 2018, and it's been over a decade since its initial release. The culprit seems to be the game's cult status.
Reportedly, Nintendo doesn't see the benefit in spending exorbitant amounts of money to localize a game they predict will only sell to a few people, especially given how much effort it would take to localize Mother 3.