Part1: Thank you for the reply! Sorry if I keep pushing the subject, but what I don't understand is Penders' disdain/hate for Chronicles. For someone who always boasts about his contributions to the Sonic IP, one would have thought he would have been elated to be the inspiration and starting point for what would become a plot and setting of the IP's core media, games. Plus, you said it yourself, to everyone's knowledge (Even Penders, maybe?) they were seen as fair game at the time of production.
Part2: I would understand if he was asking for acknowledgement/compensation, but his ownership claims seems to be made out of malicious spite, rather than a proper sense of injustice. Like if DC would have dressed Superman in a red & white costume for a few issues after the Fawcett case (I know it's not exactly the same legal case). But why do you think he acts like that? I would love to read your thoughts as you are one of the few capable of reaching unbiased conclusions when it comes to him.
So the thing with the Sonic Chronicles case is that by that point Ken had discovered Archie had lost his contract, cooked up the story that it never existed, and started filing for copyrights for his work. As such, he argued that Sonic Chronicles taking inspiration from his work was an instance of copyright infringement. In his eyes, Shade literally is Julie-Su, and the Nocturnus Clan literally is the Dark Legion, just with the names changed, and if he never signed a contract then that stuff wasn't fair game for other Sega projects to touch. To him, it wasn't uncredited inspiration, it was theft.
The case was dismissed in court because the Archie v. Penders case to determine who actually owned the copyrights for his work was still ongoing, and then by the time that was settled the statute of limitations for the Chronicles case had passed. (In basic terms: it had been too long since Sonic Chronicles came out to sue over it.) So it ended in a stalemate, with both sides still arguing ownership, and Ken would only be able to revive the lawsuit if Sega did something new with Sonic Chronicles or those characters - a sequel, a port of the game, Shade appearing in new stories, etc.
Since then, it's basically turned into a game of chicken with the copyrights. Ken believes Sega has just washed their hands of Chronicles because they don't want to deal with the legal trouble, which is honestly probably true. Meanwhile, Ken has been testing how far he can push his claims of ownership over Shade before Sega does anything, such as when he announced that Shade NFT that declared she was literally the same character as Julie-Su. (Or at least it would have if he'd ever released it.) If Sega doesn't do anything about it, then they're at risk of forfeiting the copyrights, which Ken will take as a sign that they've fully abandoned Sonic Chronicles as their property and therefore he can do whatever he wants with its elements.
So, basically, yeah, he's still just bitter and spiteful over the plot of Sonic Chronicles being based loosely on his Knuckles comics without his involvement. And to a certain extent I'd get that. Comic artists and writers are paid in table scraps and get no benefits, then they see the companies who own their work turn it into billion dollar movies and video games and mountains of merch, and they don't see a penny of those profits. They don't even tend to earn royalties off of their comics' sales. It's unfair. But while I think he deserved some form of credit and maybe some form of compensation, there's a difference between adaptation and inspiration, and Ken's just being a copyright troll here.
There's immense irony in Ken believing that Bioware's homage to Julie-Su should be seen as the same character as Julie-Su in the eyes of the law, while he's out here publishing a comic featuring K'Nox, The Legally Distinct Character Who Is Totally Not Knuckles. Also, like, one of his pet characters has always been a blatant homage to James Bond. He was out there basing Archie Sonic stories on Star Trek episodes and Superman comics and shit. My favorite Sonic story of his literally just ripped off the plot of "For the Man Who Has Everything." I don't see him out here cutting Alan Moore a check. He's nothing if not a hypocrite.