So your main focus of this image is definitely on the pokemon, so we’ll start there. You’ve captured the colors correctly, and you added a fair amount of details likes the plates. THe pokemon has shading, and gives the image a defined light source and slight 3D effect. Things that most stand out are the hands touching, in most images this doesn’t really seem to be possible based on Sandshrew’s anatomy. The blue portion of the eyes stands out far too much, it makes the sandshrew to look like it is crying.
Now here’s where the artistic style you utilized becomes limited. For the scale of the pokemon, the lines are very rough. The detail based on size along probably could have been refined by leaps and bounds, as your squares are larger than one pixel. Another major major point that this image lacks is an environment. Whether it be something as simple as a tree, a pond, a beach, the endless desert,or a rock or two, images should have something to show interaction with or give the story more background/story to it.
Sandshrew is not captured