Let me preface this by saying that I'm no master artist, a lot of the points I'll make are quite subjective but I noticed a few things in your animation and also in this image that could use some improvement
All the small stuff aside, one of the biggest things that could significantly improve your characters would be to spend more time on the posture and draft. To me her upper body posture says "I'm in a fighting mood" and her lower "I'm just chilling".
If you look at the shoulders of the character you can see that they are quite straight, this is not a problem in itself but the left arm reaches further down then the right. This could not happen if her shoulders were straight so instead it look like the left arm is broken.
Same goes for the hips, the hips are tilted which they need to be for the character to stand with one leg out like that. However its tilted the wrong way making one leg (the one she stands on) look shorter than the other.
The head also looks like it is pulled back, this is because the neck is attached under her jaw and not to the back of the head. Moving the skull to the right would fix this since it 3/4 view.
You should focus more on building your character in a simple draft where you can work these kinds of problems out before you start rendering, I would recommend doing this for animation aswell.
Animate a simple character with shoulders and hips and then redraw the character again when you render the animation using the animatic draft as reference.
Here's my version of the character with these chink's worked out(Sorry if I could not match your style precisely xD I tried).
Some things about color!
You seem to have colors and contrast down pretty well, I love the shift to warmer hues in shadows
however you did not stick to this rule, the skin goes colder in the shadows and so does the hair. With skin especially I would walk toward the red hues since there blood under the skin, even if I work with cold shadows. I made corrections to the palette in my rendering concerning hues.
Looking at the contrast both of our renders are quite flat, since we both used the same pallet and only a few values that is not surprising. I quite like flat designs in pixel-art personally so I don't have a problem with it, stops things from getting too noisy IMO
if you want to build stronger silhouettes that read well, I would look more into The Thicks and Thins.
Finally your character had a colored outline around it, this again can make pixel-are look a bit noisy, so if you want to use an outline I would stick to a solid color that contrasts your character.
Both yours and my renders have both shoulders and hips tilted the same way, if you want to add more interest introducing some asymmetry could be just the thing! Like the draft on the right.
I'm sorry I essentially wrote a wall of text but I hope you can find at least some of it helpful.