Glitching Monster Sprite in battle (due to size differences?)

I encountered a problem while importing some monster sprites that cause them to glitch in battle (In the images, the Shovel Knight's enemy has his legs cut off and the 8 colors FF3 Hedgehog pie is completely messed up, through they appear fine in both the sprite and formation editor).
As I said in the thread's title, I suppose that one possible reason is due to different size between the original enemy sprite they replace and the custom ones, but I also suspect that could be a enemy formation issue.
Some Info: Shovel Knight Enemy(8 colors): 32x40 vs GreaseMonk(16 Colors): 24x32; FF3 Hegehog Pie(8 Colors): 34x32 vs Rhodox(8 Colors): 32x32