This might not be realized until a second season pass. But I would like to have Patroklos/alpha, Xiba and any other styles from existing games. But instead of bringing the character they use existing NPCs borrowing their styles. This could be a CaS bundle instead of a character.
Also: this could alter chapters such as CoS2 Kilik vs Disciple(Xiba). Or open "side/secret" chapters such as aforementioned, Kilik vs Xianglian(Lexia)
Sorry friend, but I can virtually guarantee you that's not going to happen. Creating a skin for a character is (in relative terms) pretty simple with regard to time, man-hours, and resources expended. Creating an entire moveset, producing all of the animations, designing and implementing every element of timing, hit boxes, and attack qualities and dynamics, and then balancing that moveset against the rest of the cast...that's the truly exhausting part of the process, and probably 95% or more of the production cost.
So in essence, you're just making a wish as to which characters would appear in a season 2, since what most players care about is the style, not so much the skin. And (for reasons that you can find detailed at length in the SCVI discussion/DLC speculation threads in the casual forum, but some of which I would think would be obvious) I think it is deeply unlikely that any V styles/characters will make it into SCVI--certainly not in season 2, if we are fortunate enough to see one. Not while there are no fewer than eight SE through SCIV faces still missing, half of them with very devoted fan bases, and all of whom would flesh out the class Soul Calibur narrative being rebooted for VI. Some four of those characters will definitely constitute season 2 if we get one (or rather, probably three and a guest, I tend to believe).
Mind you, I'm just speaking to what I think is very likely to happen, but I want to make clear that at the same time, I very much like your idea. While SCV had a lot of missteps, particularly in tone and presentation and other superficial design choices, I think those movesets (as reduplicative as they were of the styles they replaced--and often inferior versions in my idiosyncratic view) should be preserved. If they could be stripped of the goofy characters they were often associated with and thus circumvent the fact that those characters come from a later era, some of them would be undoubtedly popular, as indeed they were for V. In a perfect world, where they were able to release four, five, six season passes of four characters each, I'd love to see some SCV styles return, alongside the predictable ensemble of the remaining classic series stalwarts, numerous guest characters, and maybe even some new original characters; I'd love to see a style or two return from SCIII's bonus character selection (aside from Amy, Hwang, and Li Long that is).
But realistically, we don't even know for certain if there will be a season 2 and I just doubt very much that the inertia for this model is going to carry into a season 3, let alone the season 4 and beyond that you'd probably need (presuming four characters per season, which seems likely to guide further seasons) before you got to the point where the devs felt comfortable adding back in SCV styles. I would gladly keep buying characters at five to ten dollars a pop as long as they kept making them (provided the quality remained consistent and strong balancing work was done. But the average consumer will not pay nearly that much--certainly not for long. And this multiple seasons for fighting game casts model is still new. Realistically, I think we have six more characters coming to us reliably--Amy and Cassie and second season of four. Maybe if players cared a little bit more about the core gameplay mechanics and didn't make every development company feel like they are walking into a landmine on an elaborately produced story mode (that nevertheless was destined to be silly, melodramatic, and utterly forgettable because of the source material, quality of the writing, and the goofiness of the underlying premise) we'd have a more robust roster, but the situation is what it is--Project Soul and Namco only have so many resources, and alas, no Soul Calibur in this generation was ever going to be like the new Smash Bros. bringing in the entire legacy cast. More's the pity...
Edit: Changed some wording since I guess I ought to recognize that this is someone's wish in a fantasy scenario, not a predicition on what will occur. Nevertheless, I'll leave most of the message as original put: I love the idea, but I don't see it happening.