Doesn't this go in custom modelling?
Well, anyway... there are good parts, there are weak parts.
Weak Parts
The JPEG quality of the image harms the critique I want to give, since I can't see in proper detail the model. That being said, I'll try to critique through the artefacts in the image.
It is very obvious that Amy was used as a base. That is not a bad thing itself, but the problem is, the face
IS Amy's. You got rid of the bangs, which is a plus, but the hedgehog spikes remain still under the hair. Speaking of the hair, let's get onto that.
The hair is "blockier" than smoothness of the original model.
Also, look at the character you're making a Mobian version of. The model shows a much more wilder hairstyle, on account of the fact that it's just been planted atop the spikes. While, I agree, it'd be a pain in the ass to form the hair to better match the original character, it'd pay off in the end and look much better - you can even utilise the spikes on Amy's head for this purpose. Look again at how the hair just... flows past Elise's eye in the image. It avoids the iris on the top but barely touches it on the side.
For the shape of the eyes, I would look at as much official art of Elise as possible to reform the eyes to better reflect her character, without obviously making her have human eyes.
Now, the dress. Nicely accurate initially, but all the detail is on the gold "><" design. There's nothing else. It goes down, stops and becomes something else, and then that something else stops. And goes further proportionally than it does
here. But wait, there's more. The collar of the dress could be trimmed to display the necklace. Sleeves are fine.
Not sure what's going on with the shine on the shoes, but the second image really says all I need to for this. As for the gloves, they look like that they're made of two distinct items each, and don't display any arm - like the gloves are just an extension of the dress.
There's something wrong with her left leg? Also, those shoes look like they'd fall off in motion. In addition, the color of the legs doesn't seem to match the head, but that might be the program you screencapped, I don't know.
Good Parts
The color of the irises is pretty much correct, so far as I can tell. As is the shade of brown, could do with a little more redness in it but with the way the model's lighted in the image, I suggest leaving it as is for now.