After trying out several different variants I opted to stay close to the original Sonic CD version.
I made a few modifications, primarily in the design of the limbs as well as opting to adjust his proportions ever so slightly to give him a more menacing appearance.
And i would use this as sprites and for that i'll try to mix the other artworks which it was redesigned and i'll make a fully designed and completed metal sonic while i'll find a way to redesign mecha sonic.