Poison and Roxy were originally planned to be cisgender females, but were changed during development to transgender females, due to the suggestion that "hitting women was considered rude" in America and the concern that feminist groups would sue, as revealed by Yasuda in 1993's "All About Capcom Head to Head Fighting Games". When the game was ported onto the SNES in 1991, the issue was avoided altogether by replacing Poison and Roxy with two male thugs named Billy and Sid in the American release. It can be seen in concept art for Poison that she was referred to as "ニューハーフ" (roughly translated as "newhalf"), a largely derogatory Japanese term equivalent to "shemale". [4]
A later appearance by Poison as playable character in Final Fight Revenge, an American-produced 3D fighting game spinoff of Final Fight, portrayed the character in a highly feminine manner and had her romantically interested in Cody. Commentary about her ending in the game in All About Capcom suggested that the character might have gotten sex reassignment surgery. The Final Fight-related character profiles featured in the 2005 compilation Capcom Classics Collection acknowledges Poison's transgender characterization, although it confuses transgender people with transvestites, addressing Roxy as a cisgender female who dislikes Poison's crossdressing.
The discrepancy regarding Poison has been addressed more than once in interviews with former and current Capcom employees. Final Fight designer and Arika founder Akira Nishitani stated he supposed the character could be male, but added it was up to the viewer to decide. Street Fighter IV producer Yoshinori Ono, when asked in an interview about the matter, stated "Let's set the record straight: in North America, Poison is officially post-op transgender. But in Japan, she simply tucks her business away to look female." He later emphasized it again when asked about what female characters could be included in the game Street Fighter IV, stating that it would be too confusing to include her due to the region-specific gender. Since then, however, he has changed his mind twice, first declaring her a definite post-op in all regions for better ease of localization and consistency with past official statements, and then later deciding that it's best to leave it up to the fans after all.
In early developments of Street Fighter X Tekken, footage was shown of Ryu and Chun-Li's win quotes to Poison (i.e. "Your looks really can be deceiving. I'll be careful not to fall into your trap" and "You're not very lady-like at all! I felt like I was fighting against a guy..." respectively). Other characters were later revealed to have quotes along the same lines, some even worse, including Kuma outright saying Poison smells like a man and doubting she's in any way a woman. Sometime after the footage was shown, a prominent LGBT rights group contacted Capcom about the dialogue, stating that it was highly offensive, ignorant and insensitive towards trans individuals. Capcom agreed to change the quotes, leaving only Yoshimitsu's remark about her being a "freshly-recruited kunoichi", Craig Marduk's more vague comment that he doesn't sweat the small stuff and only cares that she's attractive, and Poison's mirror match quote where she tries to recall a song, "The something-or-other in the mirror", referencing Michael Jackson's "Man in the Mirror."