the only consistently good spritework across an entire dex was in gen 2 and then again specifically in hgss for the mons that were redone (gens 1-2). everything else is so hit and miss, and backsprites have always been a toss up among every game. even in gen 4 you still didn't know if your mon would look like ass when you sent it out or would have some effort put into it to make it look interesting
>>55978923green blastoise was the best its ever looked, its a shame they never got it right again