Good interesting team. I like it all except for Gastrodon. This is just my personal preference, but I prefer Cradily as a water-absorbing special wall in sand. My set is(I use it in Sun):
Cradily(M) @ Leftovers
Trait: Storm Drain
EVs: 252Def / 252 Hp / 4 SDef
Relaxed Nature(+Def, -Spe)
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