Is Pokémon Sun on Steam?

No. Pokémon Sun is not distributed on Steam, so there is no Steam Charts or SteamDB player count for it. Its live popularity is tracked here via Twitch viewership instead.

What platforms is Pokémon Sun on?

Pokémon Sun is available on Nintendo 3DS.

When did Pokémon Sun release?

Pokémon Sun was first released on November 18, 2016.

Pokémon Sun

Nov 18, 2016Role-playing (RPG)StrategyTurn-based strategy (TBS)Nintendo 3DS

Pokémon Sun — frequently asked questions

Is Pokémon Sun on Steam?: No. Pokémon Sun is not distributed on Steam, so there is no Steam Charts or SteamDB player count for it. Its live popularity is tracked here via Twitch viewership instead.
What platforms is Pokémon Sun on?: Pokémon Sun is available on Nintendo 3DS.
When did Pokémon Sun release?: Pokémon Sun was first released on November 18, 2016.

About Pokémon Sun

Pokémon Sun and Pokémon Moon trademarks were registered thus leaking the next Pokémon game titles to the public. Pokémon.com confirmed the games would be for the Nintendo 3DS and released in holiday 2016, with a new world, new Pokémon, and new adventures. Pokémon Sun and Pokémon Moon will be the first games in the Pokémon series to allow players to choose from nine languages to play in. In addition to English, French, German, Italian, Japanese, Korean, and Spanish, players will now be able to play in both Traditional and Simplified Chinese.

Summary via IGDB.

Pokémon Sun on Wikipedia

Pokémon Sun and Pokémon Moon are 2016 role-playing video games developed by Game Freak and published by The Pokémon Company and Nintendo for the Nintendo 3DS. They are the first installments in the seventh generation of the Pokémon video game series. First announced in February 2016, Sun and Moon were released worldwide on 18 November 2016, commemorating the franchise's 20th anniversary. A pair of enhanced versions, Pokémon Ultra Sun and Pokémon Ultra Moon, were released for the same consoles on 17 November 2017.

Source: Wikipedia (text under CC BY-SA 4.0).