Is there any viable Pokémon that can learn that move before the league in gen 2?
The Pokémon obtainable before the Pokémon League who can learn Crunch learn it really late. It's probably better to just use Bite.
Steelix is probably also out of the question, since you'd need to obtain a Metal Coat (from a wild Magnemite) and then trade it.
These Pokémon can technically be obtained before the League, with Crunch, through breeding with Girafarig:
Totodile gets it as an egg move too but you'd have to have a female Totodile and breed the move onto Rhyhorn first.
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