Ursaluna is extremely minmaxed.
To my knowledge, Ursaluna is the only Pokemon that does this. The only thing I can think of that's comparable is Mega Beedrill, and in that case they were working with a strict +100 boost and Beedrill's stats are so pitifully low that they needed all the points they could spare.
To be fair, Ursaluna was only working with a 50+ BST. As Cobalt Empoleon said, the likely reason for the min-maxing was them deciding to make it a physical tank to compensate for its now numerous weaknesses. That's sadly usually a problem with Normal-type, the Fighting-type weakness is a glaring one and, with only providing an immunity to Ghost as compensation, a Normal-type Duel-type either needs to be a Type that resists Fighting making it neutral (Flying, Psychic, Fairy), has issue with Ghost-type (Ghost itself funny enough, Psychic, Bug, Poison, Fighting) or has a gimmick with Normal-type has (such as being a sound-based Pokemon); otherwise Normal is a handicap and any Normal duel-Type might as well be a mono of its other Type (Bibarel, Deerling family, Diggersby, Drampa, Alolan Rattata family, Galarian Zigzagoon family, Litleo family, Helioptile family; and now the same fate may befall Smoliv and Cyclizar). Due to what Ursaluna is based on (the Ainu god of bears and mountains, Kim-un-kamuy), it should have became mono Ground.
Fun Fact: Naganadel's Speed not being a prime number was likely done for balance.
Naganadel has 30 less BST than the other Ultra Beasts and 121 + 30 = 151 which is a prime number.
73/73/73/127/73/121, BST 540
79/79/79/127/79/127, BST 570
73/67/73/127/73/127, BST 540
Now, maybe outspeeding Darkrai would break the game, I don't Ubers, but it does seem like they could have made it work.
Prime above 121: 71/73/71/127/71/127//540
By only increasing Poipole's 67 HP/defenses to 71 instead of 73, if left enough points to have both Special Attack and Speed be 127. I left Attack at 73 as that's what Poipole's Attack was and don't want to go below Poipole's numbers.
Prime before 121: 71/83/73/127/73/113//540
You'd think going down to 113 would give enough extra points, 8, to increase one or two stats. But NOPE! The next prime number after 73 is 79, a 6 point increase leaving 2 points leftover which could not fit into anywhere. So the next prime after 79 is 83, which is 2 points above the extra points we have. HOWEVER, the prime before 73 is 71, so by lowering one of the 73 we get the points needed to raise another to 83. So, the question now become where to place them. The choice I ultimately went with more mirrors Poipole's original distribution with having a higher Attack, keeping the defenses at 73, and ultimately lowering HP to 71. Though if I wasn't following by strict rules I would have swapped the Atk and SpD, afterall Nagandel did become more Special leaning so would make sense to have a slightly higher Special Defense.
Stats more mirroring Poilpole's:
67/113/67/113/67/113
71/109/71/109/71/109
73/107/73/107/73/107
79/101/79/101/79/101
83/ 97/ 83/ 97/ 83/ 97//540
It's a very one-trick pony in-game as its best use is really spamming Pyro Ball, which is fine, but not all that fun.
I don't know, knocking out Gigantamax Pokemon with on or two Pyro Balls was pretty funny.
"BEHOLD MY POKEMON IS NOW HUGE AND ALL-POWERFUL"
Uh-huh, look my furrybait wererabbit