To summarize, it's a show where the entire world breaks, and the rest of the show is everyone fixing it. This strange
prism stone breaks into multiple pieces creating multiple "universes," and also new versions of Sonic's friends. The main goal here is to, with the help of all of these new versions of people, fix the stone and return the world back to normal. Obviously that can't happen without some major complications, otherwise there wouldn't be a show...
You can find it on Netflix, Apple TV, and Amazon Prime. I think you can also find it on YouTube, but I'm not sure.
I enjoyed the show a lot. However, (and it's always a problem with me) I wished that Sonic could've been a bit more emotional about everything. I think one of my favorite scenes in that regard is the one where Nine calls him out. Sonic is trying to save EVERYBODY, and Nine says something along the lines of, "The reason why you're so focused on saving everybody is because you know this is your fault!! You feel guilty for making your world the way it is now, and this is the only way you can live with yourself!!" Again, I don't know what he said exactly... But for Sonic to just immediately bounce back after Nine takes the prism is crazy. Shadow was telling him the entire time not to trust Nine, but he did because he felt that he was a friend. And then, he was betrayed! Not only was he repeatedly warned by Shadow, but the feeling of betrayal by someone you thought was a friend is a terrible feeling on it's own. Not to mention this guy literally broke the entire world because of this same recklessness and inability to just... listen to people. He has to be feeling terrible, and yet that doesn't show nearly as much as it should.