Short answers, pulled from the story.
Final Fantasy Legend III is a role-playing game developed and published by Square for the Game Boy, known in Japan as SaGa 3: Jikuu no Hasha. It released in Japan on the 13th of December, 1991, and in North America in August 1993.
In Japan the game was part of the SaGa series and released as SaGa 3: Jikuu no Hasha. Square renamed it Final Fantasy Legend III for Western markets to capitalize on the recognized Final Fantasy brand and grow its regional presence.
Chihiro Fujioka produced the game at Square's newly founded Osaka studio. The music was co-composed by Ryuji Sasai and Fujioka, with Fujioka contributing four additional songs while Sasai handled the main soundtrack.
As of 2002, the game had sold 650,000 units in Japan, making it the third best-selling title among the Game Boy SaGa releases.
A remake titled SaGa 3 Jikuu no Hasha: Shadow or Light was released for the Nintendo DS on the 6th of January, 2011. It was developed by Racjin under Square Enix supervision and remains exclusive to Japan, though a fan translation was developed.
Yes. The original Game Boy version was re-released for Nintendo Switch on the 19th of December, 2020, as part of Collection of SaGa: Final Fantasy Legend. It also released for Android and iOS on the 22nd of September, 2021, and for Microsoft Windows through Steam on the 21st of October, 2021.