There's a couple things in Sonic Prime I haven't noticed many people pay attention to, which is interesting because they're both focused on Shadow.
One- he actually makes an unintentional joke at the end of the show through sheer irony. His last line is "I am the Ultimate Lifeform. I go where I want." Plus the chaos control. Funnily enough, Shadow, you don't go wherever you want. That was like, his entire plot- he was stuck in the void and couldn't go anywhere, and if he tried it would physically hurt him. Way to make a joke out of irony, Shadow.
The second point is more angsty and relatea to how Shadow seeks attention from Sonic throughout the series. There's other posts out there on Prime Shadow being a bit of an attention seeker specifically towards Sonic, and it really all comes down to the fact that he's completely alone besides Sonic, what with Green Hill being gone, and now Sonic's getting attached to other people and Shadow knows he's gonna lose him if he doesn't act quick. Throughout S2 E1 (Avoid the Void if you go by episode name like I do) he repeatedly tells Sonic that his "real friends", the originals, are gone, and throughout the entire series he majorly distrusts everyone who's not Sonic, only relying on them right at the end when it's crucial to the plan. And yet, in that first episode of Season 2, he says to Sonic something that I find interesting.
"Think about your real friends. The ones who still have a chance." Who's he talking about here? Not the versions of Tails, Amy, Rouge and Knuckles- he's already stated they're not Sonic's real friends and doesn't trust them. There's no one else besides them two that survived the crystal shattering. He avoids it by using plurals, but he's less saying
"Think about your real friends. The ones who still have a chance."
More
"Think about me, I'm still here and I still have a chance. Don't just leave me alone for copies of your old friends."
Sonic, though, doesn't quite seem to get the memo- he says a bit of stuff in that episode that kinda implies he subconsciously doesn't consider himself Shadow's friend (he teases him a lot about not having friends without considering himself, among other things). Eventually, he gets it, forced into the realisation that all he has left of Green Hill is Shadow when he nearly loses him to the void. (SA2 flashbacks anyone?)
I don't remember where I was originally going with this- I think it was just about the hidden angst in that single piece of dialogue and how easily Shadow seems to be separated from the others when it's not what he wants on the inside (real) but stuff happened and I've been typing this mid meltdown so this is what you get. 🤍Happy angsting Sonic Prime fic writers
In the French Wiki of Sonic Prime, there is a rich description of Shadow's personality, and what you wrote is in there.
Deep down, Shadow feels alone and abandoned by everyone.
I might translate it later. Google is pretty accurate these days, and, even if it doesn't look like it, French is the closest language to Italian (same grammar rules and structure), just with a sligtly smaller vocaboulary, this might help.