Single post in Legends: Arceus and Unova Recolours
Here's an interactive comparison: all sprites are scaled up 4x so you should be able to see them better, and if you mouse-over or tap them then they switch to the new sprite. You should be able to really tell just how flat the original sprites are - the reason they're so flat is because in Gen V, the sprites were actually animated and so having the sprites be shaded wouldn't look good at all. Flat colours worked well with the animation, but we don't have animated sprites here so they just look... flat. Thanks to the art team, we now have shaded sprites, and this is the amount of quality improvement we're gonna be aiming for!