It's no exaggeration at all to say "Orcanos is the Landorus-T of Competitive Yo-Kai Watch 2"
There's almost no reason to not run him. He has the highest HP stat in all of Yo-Kai Watch 2 and the 2nd highest Defense stat and his Strength stat is also super high. He gets a Skill that boosts his Defense just for being front and center and being Tough Tribe makes it so his Defense can get even higher.
Orcanos is a super powerful wall in YKW2 meta.
So how come this guy goes from being everywhere in YKW2 meta to being nowhere to be seen in YKW3 meta?
He wasn't nerfed at all. His stats appear to be exactly the same in 3.
The reason you don't see him as much in YKW3 meta is actually simple.
The biggest being that in 3, magic attacks ignore Defense, making magic attackers in general much stronger compared to how they were in 2. Now any Yo-Kai that is a magic attacker with a high Spirit stat is turned into a powerful wallbreaker.
Having high Defense isn't as good as it used to be.
Orcanos's Skill was also changed slightly. It still has to be front and center to buff its Defense but now it has to be on the center TILE. Now it has to work more to get that buff especially since the center tile is the easiest to cover with Soultimates. Plus, the grid being 3x3 and standing in the center, you can't defend BOTH your teammates with a vertical link like you would with tons of other Tanks. This stuff made it so Orcanos had to compete with way more S Ranks to justify its spot on a team. It still has incredible stats and a good Skill but everything changed around it so the stuff it could usually get away with no longer works.