>>534002535
>Shadow is also thinner and more muscularly lean while Sonic is chubbier.
This is false, Sonic and Shadow have the exact same body shape. The EXACT same. They're usually built from the same character model.

>>534002535
>Shadow's quills point up while Sonic's point down.
Except Shadow's hair is the exact same as Super Sonic from the Adventure games. SA1 Super Sonic already looked like that before Shadow existed.
>The shape of his shoes are also noticeably different from Sonic's.
Cosmetic attire, irrelevant. Besides, Light Speed or Soap Shoes are comparable to the shape of Shadow's Air Shoes anyway.