Chrono Trigger plus 2.6 likely represents another ROM hack or modification of the classic Chrono Trigger. The "plus 2.6" notation indicates a version number for the modified game, perhaps suggesting several revisions. As a fan-made alteration, the original developers (Square) did not create this version. The creators of the modification are unknown without further information from ROM hacking communities.

Chrono Trigger plus 2.6

Chrono Trigger Impossible