>>29686548Right right, but it doesn't remove Steel's Poison-type immunity, just its Poisoned status immunity.
You can poison Steel-types with Poison Point, Poison Touch, Effect Spore, etc., you can poison them with Toxic or Toxic Spikes, you could even poison them with the Poison Orb. For that matter, you could even poison Komala. You just can't directly attack Steel-types with Poison-type damaging moves, because they're immune to Poison.
It's not a Poison version of Foresight or Miracle Eye. Corrosion just removes the status immunity, not the type immunity.