KidRobot is making Sonic 'mini vinyl keychains' in 2017. This panel shows all the art they are using to base the keychains off of. It includes badniks, 2 Genesis systems (compact & original) & game covers/box art.

Above you can see the retail display box you should be able to find them in, in stores. It looks nice, with large winged ring & finger waving Sonic.
What's NOT as nice, is the price tag. Each one is about 5.95. Combining that with how totally tiny they are, & that you can't control which one you get, and the price starts feeling rather prohibitivly high, especially for people who wanted to collect more than one, or are hoping for a cute Tails and having quite a slim chance of getting him.
They've chosen a lot of fun ideas with variety though. However, not everything is executed super well, note "dying Sonic" up there (why??) he doesn't really look that good. Is Orbot anyones' favorite badnick? Would you be happy paying 6 dollars for Orbot? These have been found at Barnes & Noble book stores in spring 2017.

Photo & owned by RaeLoganHere's a fan photo of one of these small keychains.
It's the "Wing Ring Title" one, and it's different front to back. One side has it in English, the other in Japanese. Notice the size of the finger here with the box: these things are super tiny & made of vinyl.
Look at the bad odds on the box sides below. Some of the items have a 1/48 chance to get it, while it lists others as ?/?? The problem is the price, it may say 'collect them all', but at over 6 dollars each and 1/48 odds that's not going to be a reasonably priced task.