Here's the treatment for a crossover idea I had, combining Sonic the Hedgehog and The Ghost Busters.
"ESPIO, CHARMY, AND VECTOR: GHOSTBUSTERS"
The story takes place in a future where the Ghostbusters are unable to bust ghosts on the scale they once did, and have begun setting up and selling franchises. The Station Square franchise was picked up by the Chaotix Detective Agency, consisting of:
ESPIO THE CHAMELEON: Smart, calm, and collected, Espio is the "Jake Kong" of the team.
CHARMY BEE: The "Eddie Spenser" of the team, Charmy's the plucky comic relief, and his fear of ghosts provides much humor.
VECTOR THE CROCODILE: The "Tracy" analog, Vector is secretly smarter than Espio and Charmy combined, though he doesn't show it much, preferring instead to lug around a dimensionally-transcendental sports bag containing detective gear and ghostbusting equipment.
THE NEW GHOSTMOBILE
This Ghostbusting team tools around in a BMW Isetta, fully equipped with ghost-sensing tools and a "boat mode". Unfortunately, it can't fly, nor can it travel through time and space. (They often resort to a cargo plane to carry the Ghostmobile around.)
And, of course, they use the now-infamous Dematerializer to banish the ghosts they battle, and receive information from the Original Ghostbusters in the form of "secret messages".