Another version of the early "Stringy Sonic" dolls. This one is different from the one at the top of the page, as he has plush shoes that have n stripe. The arms & legs are laces, giving him a wiggly & cute look, much like the very early art. 

Here's a great inspect-able photo set for one of the "Stringy Sonics", where the plush has (probably) nylon cord or some kind for the legs & arms. There are actually 3 dolls made like this. One has plastic beads for the feet, the other 2 have felt hands/feet but can be told-apart by how the face is built. (This one has the pupils further apart & smaller mouth) One of the earliest dolls, this was made in 1991 & is simple and cute. The spikes in back are 3 rows (notice how Japan dolls got them right right away, while other 3-dimensional Sonic products from elsewhere would give him a fin, 1 row etc) & are made of felt. There's plastic inside the hands/feet to keep them stiff. Notice that they forgot the stripe on his shoes. The tag says "1991 Made in Korea" with Japanese letters.