The type effectiveness of bronzong varies according to his 2 abilities:
1. Levitate = Weak to fire.
2. Heat proof = Weak to ground.
But to make this simple you can say that in-game bronzong is only weak to fire, since every in-game bronzong has the ability levitate.
Ghost & Flying. I believe that's it! Not dark or bug because although they're super-effective against Psychic, they are not-effective against Fighting. And not Psychic, because though it's super-effective against Fighting, it's not-effective against Psychic.
Water and Grass attacks are super effective against Onix.
Rock, electric, ice, and psychic types are super effective against Crobat.
Steel is super effective against rock type pokemon.
super effective is bug
Flying and Psychic are super effective against fighting
Lightning is super effective against Water and Flying types in Pokémon battles.
Ghost & Flying. I believe that's it! Not dark or bug because although they're super-effective against Psychic, they are not-effective against Fighting. And not Psychic, because though it's super-effective against Fighting, it's not-effective against Psychic.
Water and Grass attacks are super effective against Onix.
Brongzong are weak to either fire type or ground type moves depending on whether they have the Heatproof or Levitate special ability.
super effective is bug
psychic pokemons and attacks are super effective
Bug Type and Fighting Type moves are super effective against it.
Rock, electric, ice, and psychic types are super effective against Crobat.
Steel is super effective against rock type pokemon.
Bug types are super effective against Dark, Grass and Psychic (x2) in Generation II-onward. In Generation I, they were super effective against Grass, Poison and Psychic.
normal type Pokemon are not super effective against any type.