In doubles, as you know, spread attacks have their power reduced to 75%. However, if a spread attack is used against a single opponent, it should return to 100% damage. They deal 75% even if used against one opposing Pokemon if they would target your ally, as in the case of Earthquake. In this
replay, turn 15, Earthquake deals the same amount of damage to Heracross as in subsequent turns, when in reality, the damage output should have been different. Moves like Earthquake and Surf need to be recoded so they deal 100% against a single opponent; you may also want to check if Icy Wind and Rock Slide have the same coding error.
Here are the relevant parts of the replay: