I agree with the suggestions so far.
Other Possibilities:
Somber Ambush: Alolan Persian (Or Kantonese too?), Gengar, Noctowl, Ariados, Crobat, Umbreon, Sableye, Banette, Dusknoir, Rotom, Giratina, Darkrai, Golurk, Toxapex, Marshadow
Recrystalise: Vanniluxe, Crustle, Conkeldurr, Regice, Regirock, Ggalith, Diancie, Carbink, Araurus, Avalugg, Steelix, Forretress, Alolan-Sandslash, Probopass, Agron, Necrozma,
Salwart Sword:Swords of Justice, Bisharp, Samurott, Gallade, Excadrill, Scizor, Beedrill, Sceptile, Absol, Kartana, Honedge-line, Lurantis
Ion Absorb: Xurkitree, Mimkyu, Vikavolt, Heliolisk, Galvantula, Probobass, Magnezone, Rotom, Porygon-Z, Electivire, Metgross, Magearna, Plusle, Minun, Manectric, Raikou, Amphorus, Zapdos, Jolteon, Alolan-Golem, Raichu
Scrappy: In addition to the old users, Marshadow, Pichu-line (Aim for the horn!), Electivire, Medicham, Beedrill (Twin Needle used to Poison Steel types), Honedge-line, Donphan, Marowak
Technician: In addition to old users, maybe Stakataka, Magearna, Kartana, Vikavolt, Klinklang, Rhyperior, Magnezone, Registeel, Metagross, Banette, Golurk, Claydol, Steelix, Marowak, Alakazam