umm you have saved them in the wrong format use png.
Most of your sprites are good but your stantler+seviper mix looks very C+P you should have found a way of scratching the tail so it looked good
The rest look fine to me
Well both of your fusions look C+P you should use a bit of scratching to get them looking better
Your leafeon edit: One of the vines is coming out the ground, wether its supposed to come out the ground or out of him i dont know, but it doesnt look right.
And the last one is just...