Hayate
[13] Hero
If you pay attention they didn't put any major character with CAS Style. Just because they wanted to see if they can make them latter in DLC. Even EdgeMaster can appear later because he is not seen with CAS model.I can draw another parallel, if what @Sectus said before was also true, that these characters will be released in pairs, then it would make sense for Yell to be Li Long and Star to be Yun-seong, because:
Rock and Li Long (forgotten relics of the past whose styles were usurped)
Yun-seong and Setsuka (tertiary characters related to previous characters)
Aeon and Hwang (characters who are seen in-game and yet don't fight, conspicuously)
I know that Aeon has the one battle in Libra of Soul where it's actually him instead of a random Lizardman, but I really see that as a fluke, more than anything else. Aeon and Hwang feel like they were cut from the main roster of SoulCalibur VI meant to be included more than any other characters. Hwang could have easily been in, like Han-myeong, fighting with Mitsurugi's style, or even with Xianghua's style, but he wasn't seen in combat at all.
It would be very intersting to have them with a Story Arc, interracting with other SC6 chars.
For that Aeon & Hwang being DLC 8 & 9 is questionning because of that 4CHAN leaks + Vergeben explanation. Also if you look to their Season Pass model, which was 4 DLC character at each season, it really seems that DLC 8 & 9 are not in the third Season Pass, they seemed to be added after or replanned or something.