Fourthwright

i personally know nothing about pokemon myself, but i'll have a go at critiquing this piece. you've executed the idea that they just switched bodies very well by showing it very clearly in how the clothes fit their figures. however, i feel like the pink shirt on the girl on the left should be baggier and the line that you've used for the shoulder seam should be lower since she is supposed to be more petite than the girl on the right.
also, the front shoe on the right girl looks much bigger than the back shoe. if you were trying to portray that that shoe was closer to the screen, the leg should be positioned more towards the screen as well. i saw someone already mentioned how the shoes on the left girl look a little more like boxes than flats. this can easily be fixed by trying to look at references of flats. the front is always slopes down instead of the shoe being just one straight line.
the shading also could be worked on a little. i see that areas with darker shades have thicker inking lines, but you could also try executing this by not making the shading so gradient. if you look at anything around you, you can see that there is a mixture of harder shading and more softer, gradient shading. it helps to pay attention to the shading that you see on clothes and things around you <img src="e.deviantart.net/emoticons/s/s…" width="15" height="15" alt="" data-embed-type="emoticon" data-embed-id="391" title=" (Smile)"/>
i also noticed that you got a bit lazy when drawing the fingers (most especially on the girl on the left), as they look more like sausages than fingers. you could fix this by trying to find a reference online or even better, take a picture of your hand in the pose you are trying to go for (that's what i do personally).
otherwise, i actually really like the drawing style on this piece and you've executed what you were trying to go for very well. keep doing what you enjoy!

Omg no it's just what I needed D And the reason it said I didn't have anything is because you have to press the 'browse' button :3 Thanks for your critique!

dled