Concept art for Shi-Long Lang featured him shirtless, with the constellation of Orion scarred on his chest. Seems the director objected to the toplessness, even after a feather boa was added to cover the nipples.
A trailer shows Kay appearing in Turnabout Airline. Whether this means Kay would have first appeared earlier, or that Turnabout Airlines was originally a later case, is anybody's guess.
Originally the concept of the game involved Ema Skye as the protagonist and the game would focus on forensics tactics.
Concept art sketches show that Quercus Alba's design went through a phase with him looking much more like a gnarly old tree.
Fan Nickname: The Fan Translation of Gyakuten Kenji 2 localizes the characters' names as follows (Note that the translation, and therefore this list, is incomplete):
Teikun Ou = Di-Jun Huang
Gai Tojiro = Ethan Rooke
Manosuke Naitou = Horace Knightley
Mikiko Hayami = Nicole Swift
Hakari Mikagami = Justine Courtney
Yumihiko Ichiyanagi = Sebastian Debeste
Tateyuki Shigaraki = Raymond "Ray" Shields
Souta Sarushiro = Simon Keyes
Shuuji Orinaka = Jay Elbird
Marie Miwa = Patricia Roland
Ryouken Houinbo = Sirhan Dogen
Issei Tenkai = Jeff Master
Tsukasa Oyashiki = Katherine Hall
Isaku Hyoudou = Isaac Dover
Paul Holic = Pierre Hoquet
Delicy Scone = Delicia Scones
Yutaka Kazami = Dane Gustavia
Touko Mutou = Karin Jenson
Otome Itami = Bonnie Young
Tsubasa Kagome = Jill Crane
Bansai Ichiyanagi = Blaise Debeste
Borumosu = Moozilla
Shimon Aizawa = Johann "John" Marsh
Ryuji Kamei = Jack Cameron
Also falls under Fan Nickname: The Let's Translate on YouTube, also done by a fan of the series and one who worked on the Fan Translation team, uses the following localized names: