Gastrodon does not learn Earthquake naturally, but it can learn it through use of a TM.
Sorry but you have to teach it to him by a tm or something because ive searched and searched but every websit says he doesnt learn it naturally. :(
No, Darkrai is not able to learn Earthquake.
Yes, Gallade is able to learn Earthquake through the use of the Earthquake TM.
metang doesnt learn earthquake.
Aggron can learn earthquake by using the TM on it.
Yes, it can learn it by using the TM Earthquake
Nidoking can only learn Earthquake when you use TM26 on it.
It doesn't learn Earthquake through level up, but it can learn it through the use of the Earthquake TM.
Venusaur can only learn Earthquake through TM26 Earthquake.
Earthquake is TM26
Rampardos can learn the move Earthquake though not by leveling up. You can teach Earthquake to Rampardos by using the TM 26 on it.
Numel does not naturally learn Earthquake in its movepool. However, it can learn Earthquake through TM26 in Pokémon games, starting from Generation III.