The problem with Chrono Trigger is that Square Enix isn't the sole rights holder of the title. Bird Studio (Toriyama Akira's Studio), Shueisha (best known for Jump Comics), and Armor Project (Yuji Horii/Dragon Quest) all hold rights to the title. You can see this on the bottom of their homepage.
The game was conceived as a "Dream Project", where an all-star team of game developers, musicians, and artists made their dream game. The game was also heavily marketed by Shueisha, where Jump Comics was in its 'golden age' pumping out hit after hit; Dragon Ball, Naruto, Once Piece, Yugioh, JoJo, Slam Dunk, HunterxHunter, etc. V-Jump and Jump was Chrono Trigger's hype builder in the 90s, especially as its star artist, Toriyama Akira, of Dragon Ball and Dragon Quest fame was doing the art.
For that reason there are a lot of people that need to sign off on making remakes and re-releases. Its also the reason why Square changed the name of the game to Chrono Cross for the sequel instead of making a Chorno Trigger 2 which would have been a guaranteed success based on the brand.
Its not an impossible task, as we do have an iOS and Android rereleases, as well as various versions, but we don't have any remakes, sequels, or collaborations. There are a lot of people will want to get paid and need to sign off for that to happen.