Theme dolls with a...traditional motif. They are meant to be Taiko Drummers. A mini-traditional drum is in the background, maybe they are celebration related? The differences seem to be in the dolls head bands. A curious set- it says "Sonic" probably "and Tails"
at the top, but maybe the first word explains it. 

In the gallary you can get a closer look at the Tails from the set. He looks ok, if a bit odd with a headband across his eyes, and the little suit. A tad of over-kill on his facial edges becomes evident, but the double-shine-spots in his eyes keep him cute looking. The early clothed plushes helped capitalize on more plush sales, though they only had 2 main characters to work with, 3 if you count the rather scarce Eggman.