Gonna drop in with a quick fact check. "Ami" does mean "friend" in French. "Mon ami" is "my friend." "Bon ami" is "good friend."
And to add to the discussion... Fanon is perfectly fine. I write and draw a good bit of fanon. But, I don't claim my fanon as original ideas. They may be original fanon, but they're still fanon. And your characters fall into that fanon category. If you wanna write fanon, that's fine. Everyone writes fanon.
But don't claim that your fanon is entirely original. It's one thing to make fan characters, it's another to rip off of other stuff and claim ignorance to the source material. There are such things as copyright laws, and if you decide to publish your game in its current state, you would be breaking copyright laws. Seriously, as others have said, you need to take a step back and reevaluate your work. Take breaks from Sonic games for a while as well. Don't totally shut yourself off from everything though, just start working at getting inspiration in other more legal ways.
I'll be honest with you, there are no original ideas out there anymore. Everything's been done. But, what people do is put an original spin on an old idea. What can you do to make your stuff original? Use your imagination. Think of a situation in your game's story and then think of different ways it can be done. As for your characters? To be blunt, the names need a serious overhaul. Not every name has to be Japanenglish. Don't tie your characters down to one nationality. Broaden their horizons. Be creative.
We're not telling you this to pick on you. We're trying to help. Whether you wanna accept the help is up to you.