Yeah, but Negan was added to Tekken 7, remember?
Yeah, and I'd agree that of all the guests who have apepared in Namco first party fighters, he's the one that shows how far Namco is willing to stretch itself to make someone fit, but let's be clear that these situations are not at all similar with regard to the IP, the parties, or feasibility/likelihood of a character transplant as either business or aesthetic matter. Neegan, at the end of the day, comes from a comic book (though the character image for Tekken is stylized closer to his television appearance): he fits pretty well from the start with the cartoony/over-the-top-villian violence of the Tekken franchise. Or at least Neegan fits much better with the style of Tekken's action than any GoT character ever would with Soul Calibur, since GoT characters come from a world where, if you're getting weapons stuck through you, you better have one of those especially powerful red priests in your corner, if you want to see the next day; Soul Calibur character are expected to take 50-100 sword strokes through the vital organs per match, and then pick themselves up without even being winded.
You may note that there is one GoT character who actually does more or less fit those aesthetic demands who may therefore, in theory, represent the best bet for a SC cameo: Undead Gregor Clegane. But it's still not going to happen, because, at the end of the day, the biggest road block here is not the style contrast, it's the fact that GoT is the hottest IP on planet earth right now and under the control of at least a half dozen entities that are going to have some say over any licensed content coming out the show--and all of them are going to have reasons to be cautious about diluting the brand with silly cameos in anime-fantasy sword fighting games.
In order to get Neegan, Namco had to license a character from Robert Kirkland and maybe AMC, with some image rights royalties possibly going to Henry Dean Morgan--all for a kinda-sorta well known character from a show that was a minor hit six years ago or more. Compare that against trying secure a license from George R.R. Martin and HBO for the rights to a character from the biggest television phenomenon of the last decade. If those parties wanted to cash in on a series of games that were flashy fun, they would have done so already; developers and publishers would have been lining up out the door for the last eight years to work with them on anything that the brand could have been slapped on. Instead, the licensed games so far have been in TellTale style narrative games and strategy games--none of which are hot sellers, but those formats better fit the expectations of the tone of the world that GoT/ASoIaF take place in.
TLDR: I don't see Martin greenlighting an appearance of Jon Snow in a game where he fights ninjas and androids, and even if he was (against all odds and indications) willing to, insofar as the versions of those characters are based on the show's variants, that brings in all kinds of other players.
And it's not like this Elden Ring announcement suggests some kind of cozy relationship between Martin and Namco; FromSfotware (a third party studio) has contracted Martin as a "consultant" for Elden Ring, meaning he's an employee (a consultancy almost certainly means Martin will not be retaining any character rights relating to his work with the company developing the world for this game, and that such characters will not be based off of concepts from Martin's pre-existing works, which would need to be licensed). Basically FromSoftware is purchasing the right to stick Martin's name on the product just on the hope that it will boost the profile of the product--that's valuable to them regardless of how much or how little Martin actually ends up contributing to the world-building of the game. That same developer, as a company, has entered into a contract with Namco to publish that game, in substantially the same way any third party developer and publisher do.
There's absolutely zero indication here of any kind of working relationship between Martin and Namco, nor any direct contractual connection. So there's not really even a tiny bit more reason to expect a GoT character to show up in a SC game now than there was before Elden Ring was known about.
Sure, its not a 100% confirmation
I mean, it's not even remotely anything like a confirmation, to be blunt. Also, there was a never a "rumor" (that I heard anyway) that a GoT character was in development or being negotiated for; just random speculation here (and maybe on other forums for all I know) that such a character would be (in the view of some) "cool". I don't think such a character would ever be considered for, or work with, SC (Zombie Clegane would be interesting I suppose, but difficult to make work as something that didn't step on Nightmare and Astaroth's toes), but regardless, we've never had any kind of indication that such a thing was in the works or even being discussed between interested parties.
