I actually haven't edited the original sprite at all. I think it's just that my custom followup frames are lacking some of the nuance that made it look Z2. I guess it's easy to fall into that sort of pitfall when you're building off of someone else's work. I must ask though, why is the palette different in your comparison image? That kind of kills the contrast between two of the shades and makes the sprite look like it has less colour depth than it actually has.
And yeah, it moves pretty wobbly. Maybe next time I should try animating something less subtle than a stance animation.
Cleaned up the animation I made a while back for Ethan The Human & Balthazar's Trunks sprite. It's a bit messy in places but I'm out of stamina now xD also idk what happened with the white border thing but whatever