Don't know where you heard that, but no, Sedona has not been in any oneshots to my knowledge. There is this old twitter post however:
https://x.com/izumimitsu1102/status/1268468786153259012
So we know that Sedona and Birou were the first two designs ever made for the series, and that Sedona was definitely a girl when first created. It seems to me that early on being a Kafna was envisioned as a purely female profession, what with the oneshot's cast being female and the uniforms having dresses(in fact, if you reread the first few volumes you can see the design change over time from baggy pants to being far more slimmed and conveying a more unisex design).