Meanwhile, Nintendo's remake of Paper Mario: The Thousand-Year Door debuted at second place in the monthly charts.
Three-Point Challenge is playable solo and for up to four players. Local and online play is also available for two-on-two matches.
NSO subscribers can play Ubisoft and Nintendo's acclaimed turn-based tactics title at no additional cost for the next week.
The remaster was also accompanied by Luigi's Mansion 3 re-entering the top 10, taking the No. 7 spot.
Luigi's return to Evershade Valley is a welcome one.
It is the second-fastest selling Nintendo Switch game of the year in the UK, behind Paper Mario: The Thousand-Year Door.
The Pokemon Company previously said that it would "investigate and take appropriate measures to address any acts that infringe on intellectual property rights related to Pokémon."
The upcoming HD remaster for the Nintendo Switch will not be sold at a lower price, as some may have hoped.
The multiplayer party title will launch exclusively for the Nintendo Switch later this year, in October.
Tantalus Media previously also worked on The Legend of Zelda: Twilight Princess HD and The Legend of Zelda: Skyward Sword HD.
In comparison, Donkey Kong Country: Tropical Freeze has a file size of 6.7 GB of the Nintendo Switch.
The turn-based RPG will launch exclusively for the Nintendo Switch later this year, on November 7.
However, it won't divulge the studio developing the title, asking fans to "please stay tuned to the game credits at release."
The game's recent showing was reportedly showing 900p gameplay, same as last year's Metroid Prime Remastered.
The newest traditional, top-down entry in Nintendo's action-adventure franchise will launch for Switch this September.
Here's everything you should know about the Zelda series' next mainline 2D adventure.
The game's official Japanese teaser website has revealed some additional, new glimpses of in-game footage.
The Polish studio is known for publishing remade classics like Front Mission 2: Remake and The House of the Dead: Remake.
The special edition console, which will come bundled with 12 months of Nintendo Switch Online + Expansion Pack, will launch alongside the next Zelda game.
Complete Super Mario Bros. in one run as a Legend Challenge or compete with the ghost data of other players in a game of Survival.
