Topic: I got an idea.
I was thinking: if Sonic X-Treme was finished and released back then, Shadow would've never existed as all the games would have been in the Classic style these days (like Sonic Mania, I guess? Or the Classic stages in Sonic Generations and Sonic Forces.) I wish Sonic X-Treme was released, but at the same time, I love Shadow. Then, suddenly, I had a great idea: what if Shadow debuted in Sonic X-Treme instead of Sonic Adventure 2? Of course, he wouldn't be in the series now if that was the case, but we're finishing Sonic X-Treme, so...
I actually was talking in the Sonic Discord server a few days ago about what Shadow would be like if he debuted in the Classic games, and what if he debuted in Sonic CD replacing Metal Sonic. I guess the role I brainstormed for him there would work here, so allow me to copy and paste this edited Sonic CD US manual and JP Sonic CD character profile I created for him...
Princess Sally shrieked as she was snatched up, and she and her captor vanished in a black streak of light!
"What the -- PRINCESS SALLY!"
It didn't take long for Sonic to realize what had happened. "This has to be one of Dr. Robotnik's tricks!"
But it wasn't. What really happened was that the vehement Shadow the Hedgehog was on the hunt for Sonic, as he believed himself to be the fastest hedgehog in town. Upon seeing Sonic's speed, he immediately became jealous and set about tracking down the blue blur to do horrible things to him. Once he saw Sonic approaching Little Planet, he dispatched himself to grab Princess Sally and lure his arch enemy into danger.
"How convenient!" Shadow snickered, teleporting in front of Sonic. "This time my maxxed-out momentum will crush you! Oh, don't forget: Dr. Robotnik's taken over the Little Planet, too. Once all the Time Stones are in his... or my... hands, one of us'll be able to manipulate time and conquer the world!" Even though Shadow thought he was so important and wished to conquer the world himself, he had to give credit to Dr. Robotnik for allowing there to be a chance to do so. "HAW, HAW, HAW, HAW!" he crowed before teleporting away.
Sonic stood on a rock and though. Robotnik had control on the Little Planet, Shadow had Princess Sally, and soon both would have the Time Stones...but not if Sonic got to them first!
Shadow the Hedgehog
Gender / Male
Age / 16
Personality / Self-important. Vain.
Special Skills? / Air grinding
A teenage narcissist who refers to himself as "the ultimate life form." His abilities are the same as Sonic's, and what's more, he can put out speeds faster than Sonic in an instant. Envious of the speed he possesses, Shadow regards Sonic as an enemy.
So Tiara nor Amy wouldn't be kidnapped by him in Sonic X-Treme, but they'd be fighting to stop him and/or Robotnik from taking over the world.