Clefable @ Leftovers
Ability: Magic Guard
EVs: 252 HP / 252 Def / 4 SpD
Clefable is amazing. It has high HP and SpD stats. It's also slow, which is good because it can take hits for other members of the team and get a clean switch with Teleport. Soft-Boiled gives it instant healing, and it can cause status with Thunder Wave or Toxic. Due to it's fantastic ability, it can't be Toxic Stalled itself. Clefable can also function well as a Wish passer with Teleport.
Thanks to its extremely wide movepool, Clefable can provide teams with many forms of utility, be it setting up Stealth Rock, crippling foes, or supporting teammates. Its ability makes it a reliable status absorber and as such a solid switch-in to Pokemon like Toxapex and Mandibuzz, while its typing makes it a decent check to Urshifu-S as well.
(Normally I would say Toxapex but....Water-type)
(This is Smogon's set.)
Mandibuzz @ Heavy-Duty Boots
EVs: 248 HP / 160 Def / 44 SpD / 56 Spe
-Defog/Brave Bird/Knock Off
Mandibuzz is another awesome wall. It has nice HP and Defenses, with 100/105/95 respectively. It's ability (Overcoat) allows it to be immune to Powder moves and weather chip damage. Mandibuzz can serve as a valuable Defogger, even with hazards being less prevalent. Knock Off removes needed items or Brave Bird is strong STAB. U-Turn is a great pivot move. Foul Play is always nice for physical attackers.
Celesteela @ Leftovers
Nature: Bold/Calm (If you want a Def boost from Beast Boost, use Bold. If you want a SpD boost, use Calm.)
Ability: Beast Boost
EVS: 252 HP / 128 Def / 128 SpD
Celesteela has long been a good staller. It has access to Leech Seed and Toxic, taking away massive chunks of the opponent's health each turn. It's pretty hard to kill. Celesteela has as many offensive options as defensive ones, but I thought it was worth mentioning.
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