Hwang and Aeon are effectively a given. I’m not sure if anyone is disputing that.
Hwang is representing a style we don’t have in SoulCalibur VI, despite the fact that originally he was a variant of Mitsurugi (SoulBlade), and then a variant of Xianghua (SoulCalibur). That being true, he wasn’t really a variant of either Xianghua or Yun-seong in his SoulCalibur III appearance. He was very firmly his own thing, with or without Yun-seong. But we don’t even have Yun-seong, if you wanted to claim a variant, due to Assassin (who would evolve into SoulCalibur III Hwang) having some inspiration from Yun-seong.
Aeon is a variant, though he’s a unique variant that no one else can really do the same as him, due to his lizard status. It seems very unlikely that it will be dual axe wielding, fire breathing, Kratos angel wing having Aeon from SoulCalibur V, but a return to his shield form, when Aeon was a variant of Sophitia. His primary weapon would be a sword (Xi Sword is clearly in his story art), even, with axes as secondary selections. So this is a third sword and shield wielder, and yet, all three will be quite different. I’m expecting Aeon to be far more advanced than Lesser Lizardman, being the most reptilian he’s ever been, to really sell the uniqueness.
Yun-seong and Setsuka are not variants, and they are highly requested and beloved.
Yun-seong was absolutely introduced as a unique character, instead of leeching off Hwang. He would be a Hwang variant in the same way that Cassandra is a Sophitia variant. Which is to say, not at all. Him being a “hard sell” when you already have Hwang in the pack gets outshined by his sheer popularity. More people are aware of Yun-seong simply due to SoulCalibur II being the most popular entry point to the series. The only way it would be suspect would be if Hwang and Yun-seong were released as a pair together, and there’s no way that they would do that. It’s helped further if Hwang is first and Yun-seong is third, to give them some distance.
I really don’t think I need to offer any defense for Setsuka, so we’ll move on. The only thing I can add is that they may wish to “finish strong”, like they’re doing with Cassandra right now, to keep people on the hook, as to why she would be in the third pair.
Li Long and Rock, then, are likely the hardest sells, I’ll grant you that. But it’s also because of that, that it makes the most sense for them to be released second, in the middle of the pack. Their inclusion is in the interests of completing the classic cast, as only them being missing would be incredibly suspect. But let’s dive in.
Li Long, as I mentioned before, has a couple of different options. He can wield dual nunchaku, like his SoulCalibur III appearance, and he has more uniqueness going for him than the other variants. His style is also very composed and precise, compared to Maxi’s flamboyance. That, or he could take up the three-section-staff, to be something totally different, which would also lend itself to being more grounded and “strong” compared to Maxi’s agility.
Rock is the one that is truly the hardest to justify, considering that Astaroth is a golem crafted in Rock’s form, and now more than ever, Astaroth took a lot of Rock’s traits, considering that Astaroth was the heavy hitter and Rock was the grappler. They both had both before, don’t get me wrong, but there was a clearer divide, where Rock had far more grapples, and yet SoulCalibur VI’s Astaroth has more grapples than ever before, so it’s hard to say what Rock can possibly bring to the table. This may very well be the weakest link of season two, but they may also be able to pull something off to make him stand out. Look to Seong Mi-na for inspiration that it’s possible.
Getting these six, the only characters left we would not have would be Algol, Dampierre, and Hilde, and they’ve got to save someone for SoulCalibur VII.
