When running Career Mode with Agnes Tachyon and completing the Satsuki Sho at 5th place or better with a Normal Mood or worse, a unique cutscene will play. In it, she will request that her next race be changed from the Japanese Derby to the NHK Mile Cup, and this will also change her current goal to the latter. However, given her default low aptitude for Mile Races at rank D, this makes it likely players will fail the career and force early retirement. This is likely a reference to the racing career of the real-life stallion the character is based on. In 2001, after winning the Satsuki Sho (the first race in Japan's Triple Crown series), Agnes Tachyon was retired early after he developed a bowed tendon, and thus never entered the Japanese Derby nor got the chance to win the Triple Crown.

To promote the game's North American release, publisher and developer Cygames partnered with the Churchill Downs racetrack as a sponsor for the 151st running of the Kentucky Derby on May 3, 2025, featuring a booth with a demo of the game and other Cygames releases. They also acted as the sponsor to the Unbridled Sidney Stakes race the day prior, with the Cygames logo featured on the starting gate and saddle towers of the horses.

There are two versions of the early concept art for Hishi Amazon's Race outfit with and without her wearing undergarments, with the latter version sporting noticeable tan-lines. The pantless design was first used around the time of the character's reveal in 2017 and was replaced by the censored version seemingly around 2018. The pose she makes in this concept art appears to be a reference to the pose made by the titular main protagonist of the 1974 Japanese TV series "Kamen Rider Amazon", who she shares the name Amazon with. Neither version of this design would be used in the final game as it was instead redesigned completely.