Smogon was less helpful than usual this time, so I had to do some of my own research.
Better wide guard users: Smeargle, Pelipper, Mienshao
Iron Valiant is worse than Mienshao because Mienshao is just better. Seriously, CC from Mienshao, thanks to Inner Focus, can OHKO Incineroar, yet Valiant can't. Pelipper provides a bit more utility, with rain and Tailwind also being option.
Better icy wind uses: Latios, Flutter Mane, Iron Bundle
Latios has higher special defense, and its typing makes it much better at checking Amoonguss and walling water attacks. Flutter Mane has better special defense and speed, and its typing makes it better against both Calyrex forms. Iron Bundle has higher speed and its STAB moves (especially freeze-dry) are super effective against a lot more Pokemon.
Ninetales is a better screens user because it can set both screens at the same time.
Whimsicott is a better encore user because of prankster and tailwind.
Quick guard isn't useful because priority moves are rare. Spirit break is outclassed by stuff like snarl and struggle bug because they can hit both opponents.
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