Because the game's 40 playable characters all have different speech patterns, a sub-program was created specifically for the game to generate the different speech patterns around the line, rather than code in every line for every character.
In the US/Canada version of the game, after completing the game once players may encounter a battle with three characters returning from Chrono Trigger (1995): Slash, Flea, and Ozzie. These characters are (obviously) named after rock legends: Slash of Guns 'N Roses, Flea from the Red Hot Chili Peppers, and Ozzy Osbourne. They are also a mistranslation; in the original Chrono Trigger, they were named after condiments (Mayonnaise, Vinegar, and Soy Sauce). However, thinking that the joke would not go over well, translator Ted Woolsey changed the names.
Translator and Localization director, Richard Honeywood created an auto-accent generation system for the game where they could write in plain English text and allow a randomly generated accent to come out. Without this system the text for all 43 main characters would have made an English translation impossible.
Some of the tracks in the game are remakes of tracks from Chrono Trigger (1995), including the world map theme in Home world and the victory theme.
Despite its large cast or characters, several playable characters were cut from Chrono Cross. This could explain why some random characters have portraits, such as Leah's sister.