Hmmm...you really have a lot of potential, because for beginning sprites...they are very good. Here's where the constructive critism comes in. (Don't be scared, when they are really good sprites, i like to pick 'em apart to make them better XD)
Fakemons: I think that the anatomy is slightly 'lumpy', because the body is very uneven...I'm not great at scratches. Also, the outline is somewhat luminescent, and in order to make them look more official, you should use a slightly darker outline in places.
Fusions: In general quite good. There are places where the sprites are a little 'cut-and-pastish', and the outline could use a little redoing. Remember, that you will always need to tweak shading/outlining a little bit when fusing.
Revamps: Really very well done. The main problem is that they have a very light outline, so they don't look like they are official sprites.
Reposes: These are alright. The Grovyle one looks very wrong, because the sprite looks squished, and the stomach has a weird shape to it now. The Stantler is very well done...I really can't critique it that much. The Deoxys looks good as well.
Great Job Though...I just love giving critique to good sprites, because it makes them look that much better. Keep up the good work!