Klefki or Meowstic for Gen 8 UU?

Question

Gen 8 UU both prankster Pokemon.

Answer 1

If you want an offensive Pokemon, choose meowstick. If you want a set-up mon, klefki is perfect.
The ability prankster is only really useful when using non-attacks and if the Pokemon you are using is an attacker, then it's not as valuable.
This is why klefki is commonly used in uu, while meowstick lurks in tiers a bit lower.
Klefki has spikes, stealth rock, thunderwave, screens and an amazing defensive typing.
Meowstick lacks ability to make entry hazards and Klefkis great typing.

Klefki is more viable, by a long shot.

Comments

Note that gen 8 UU doesn't allow Light Clay and so Screens aren't that good.

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What about OU?

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OU does, but it has way better screeners available like Tapu Koko  and Alolatales.

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Klefki doesn't learn stealth rock and is not common in UU. Last month, less than 0.9% of teams used it.

Answer 2

Don't use either. Both are bad.
Sure, Klefki might be a little bit better than Meowstic in UU, but the difference is so small that Klefki is still almost never worth using. First, screens are pretty useless when defog is common and light clay is banned, so Klefki's only useful setup move is spikes. This makes Klefki outclassed by Skarmory and Scolipede.
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Skarmory is one of the key defensive pillars of UU thanks to its sky-high Defense, reliable recovery, and amazing defensive typing, checking dangerous offensive threats like Excadrill, Zarude, Scizor, and Gyarados with ease. Skarmory has a bevy of utility moves. Spikes wears down defensive threats like Hippowdon and Chansey for its team, and Skarmory can set Spikes easily thanks to its defensive utility and good matchup versus Excadrill. Furthermore, Whirlwind prevents Pokemon like Dragon Dance Gyarados and Swords Dance Scizor from setting up, while Iron Defense alongside Body Press allows Skarmory to improve its matchup versus threats like Azumarill, Swords Dance Scizor, and Conkeldurr. Skarmory can even run Defog on stall teams thanks to its great matchup against entry hazard setters like Excadrill and Hippowdon. These traits, in addition to its synergy with top defensive picks like Amoonguss, Slowking, and Chansey, allow Skarmory to fit on a wide range of archetypes ranging from bulky offense to stall.

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Scolipede is able to get Spikes up easily for hyper offense teams with its Speed and can keep them up with its coverage and Endeavor. Poison Jab is most notably able to hit Hatterene hard while also hitting neutral targets like Azelf, Hydreigon, and Thundurus-T. Earthquake dissuades Cobalion from setting up on Scolipede and hits Rapid Spin users like Tentacruel and Excadrill. Endeavor is useful against bulkier Pokemon such as Chansey as well as Defog users like Salamence. Speed Boost stops lead Excadrill from spinning away the Spikes and outspeeding Scolipede afterwards. It also lets Scolipede set multiple layers of Spikes against Choice Scarf users like Diggersby and Hydreigon.

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