Well, the main issues I see are some of the proportions and shapes seems a bit off.
Like the legs for the main protagonist seem a bit small and thin for him, and the head and legs of the first Galactic sprite on other ends of too small and too big respectively. Those are the biggest ones I noticed
If you/whoever sprited them scratched sprited the first one, I do give major props. I don't scratch sprite, instead, in order to keep structure proportional and looking good and real, I usually combine official sprites and edit them to no end until I get what I want. Yours here looks good, but also not quite styled like pokemon imo.
Any problems I see and mentioned are things that I see as just off. If those could be worked out, then the sprites (especially the main character sprite) could look great.