An interesting question though, is what will happen to Knock Off? Will it's utility still make it worth using over Frustrations much higher power?
It's a 4.5 BP difference when removing the target's item. People will still run Knock Off, probably some of them pair it with Return, since Dark and Fighting are both vulnerable to Fairy, with Fairy being the only type that resists Dark without being vulnerable to Fairy. (And it's not resistant)
Fake Out
Overally utility: much higher.
Five Four different super effectives is much more threatening, and Fake Out is
very common on Fighting types as is, so they appreciate the STAB. Yeah, more things resist Fighting than
error: type missing Normal, but Fake Out's main values are
1: Forcing switches
2: Breaking Sashes/Multiscale/Sturdy
3: Free damage!
4: Blocking certain events from happening, particularly in Doubles. (eg stopping Trick Room, Tailwind, etc)
Of these, free damage is the only one that particularly suffers.
One big hit to Fake Out's utility, however, is against Talonflame -normally Fake Out is one way to push damage through on the bird when desperate, priority Brave Bird or no, and it resists Fighting, halving your damage output. Even for Fighting types, it's still only 75% of the damage that
error: type missing typed Fake Out does.
Ambipom is one Pokemon particularly unhappy with the change, since it actually could output
very impressive damage with Fake Out, between Technician and STAB, and it often ran
error: type missing Gem to bolster it further, allowing it to do more than 50% on some fragile targets. It also hurts that now Ambipom is basically completely walled by Fairies -Fake Out is resisted, its STAB is resisted, and U-Turn is resisted. So unless Quick Attack or something becomes Steel or Poison, Ambipom will really struggle to deal with Fairies. On the other hand, a Ghost switching in to block the Fake Out is asking to be ripped apart by TechniBite, so eh, Ambipom is probably basically happy.
Return and Frustration
Now people won't pick Frustration just to screw over Ditto.
More seriously, Dragon, Fighting, Dark, Ghost, and Psychic all take a big hit, with every random physical attacker having impressive coverage against them. On the other hand, tons of stuff runs Knock Off anyway, and it's only slightly weaker when removing an item, so eeeh.
More important to me is: Fairies can run
real Physical STAB (Diancie cheers with joy! Physical set is possible!), and never worry about missing while throwing in a free power boost. (Who cares about Play Rough's chance to lower Attack?) And more generally, again, Dragon, Fighting, and Dark now have near universal coverage against them from physical attackers, which is
not true in standard play. Tyranitar is glad to replace Crunch with Frustration -but it's not so glad that literally any Physical Attacker may spring a 102 BP Super Effective attack on it without warning.
(Mega) Kangaskhan
Ground/Fairy is very nearly perfect offensive coverage (Only some Levitators, Flying/Steel, Flying/Fire, and Flying/Poison laugh off both), and Kangaskhan already runs Sucker Punch or Crunch anyway. (Screw you Bronzong) A probable set for Mega Kangaskhan would be Fake Out/Return/Earthquake/Sucker Punch, and now Ghosts can't wall it at
all. (Even Gengar just gets mashed with Return, resistance or no)
Basically this thing is a monster, more so than ever. Ground/Fairy is even mildly complementary on the defense, with Ground covering up the Poison weakness on Fairy.
Aaaand I don't really care about any other changes made thus far. Stantler is probably invalidated by an array of other Psychic types (There are
way too many of the things), and I already covered Ambipom in talking about Fake Out.
