You can use dual type Pokemon but if it repeats on another type, you can use another Pokemon of that type but you have to mention the repeated Pokemon in between ().
Normal: Azurill (195) Fire: Slugma (250) Water: Wishiwashi-Solo (175) Electric: Pichu (205) Grass: Sunkern (180) Ice: Snom (185) Fighting: Tyrogue (210) Poison: Weedle (195) Ground: Wooper and Wooper-Paldea (210) Flying: Combee (244) Psychic: Ralts (198) Bug: Blipbug (180) Rock: Rolycoly (240) Ghost: Shedinja (236) Dragon: Noibat (245) Dark: Poochyena (220) Steel: Diglett-Alola (265) Fairy: Azurill (195)
Hope I helped!
This is Based off of PRIMARY typing Normal: Azurril(190) Fire: Slugma(250 Water: Wishiwashi solo(175) Grass: Sunkern(180) Electric: Pichu(205) Ice: Snom(185) Fighting: Tyrogue(210) Poison: Weedle(195) Ground: Wooper(210) Flying: Combee(244) Psychic: Ralts(198) Bug: Blipbug(180) Rock: Rolycoly(240) Ghost: Shedinja(236) Dragon: Noibat(245) Dark: Poochyena(220) Steel: Alolan Diglet(265) Fairy: Cleffa(218) Note No Pokemon has fairy as their primary typing except for pure fairy types and Cleffa is the weakest pure fairy type so that's why its here instead of azurill.