Meloetta is super cute and nicely designed~ >w<
My favorite is probably Jirachi... I first saw him in a Pokemon guidebook and the aspect of a wishmaker sounded really nice Plus it's the cutest Legendary and its name reminds me of Tamagotchi! But I adored Jirachi before I knew he was a legendary or that he was popular XD
Out of newer Pokemons I really like Meowstic... I adore cats and psychic stuff even though I'm not usually fond of the Psychic Pokemon type
When I was young and just watched the Pokemon anime, my favorites were Wigglytuff, Jigglypuff, Butterfree, and Psyduck.
my favorite pokemons are sableye and jirachi mainly because sableye with its hidden ability can drive anyone crazy and jirachi is a perfect paraflinch pokemon.
Both pokemon were really good, until fairy type was introduced and ruined sableye's no weakness status and electric type pokemon being resistant to getting paralyzed, messing up jirachi's paraflinch combo. i dont hate fairy types or anything though
Both sableye and jirachi are still my favourite pokemons even though they arent that great in battle anymore
If I had to pick just one it would be Totodile. I love him so much ever since I played Pokemon Gold when I was little! Other than Totodile, I really Like Venipede, Scolipede, Chingling, Sableye and Froslass
flaaffy is the Pokemon I feel connected to the most, so the entire evolutionary line is my favorite I guess. other than that Jirachi and the the Shinx line take second place because of their respective emotional value that they hold for me. It has nothing to do with cuteness, stats or success, only personal experiences.