Yoshimitsu just felt a little too tricky and technical for me to use. It just wasn't working out for me in practice mode and in matches. I always loved watching competent players play him but I know I'm too horrible of a player to play him right lol.
When it comes to fighting games, I usually have characters whose character I actually like separated by characters whose moveset I enjoy playing.
According to a wiki, it was the other way around. Edgardo's 3D model was finished but his moveset wasn't ready.
https://soulcalibur.fandom.com/wiki/Edgardo
According to Hideo Yoshie, current SC6 art director and longtime SoulCalibur visual designer, Edgardo was supposed to be a double saber character in SC3. His moveset eventually made it to SC6 in the form of Grøh.