So I've been using the LearnEggMoves component of the mod and I've noticed that Marill and Azumarill can only be taught egg moves that Azurill can learn, however there are egg moves that can be bred onto Marill (when not using the Sea Incense) but not onto Azurill. Specifically, these moves should be Amnesia, Aqua Jet, Belly Drum, Future Sight, Perish Song, Present, Superpower and Supersonic. There might be similar issues with other Pokemon lines where the pre-evolution is bred using incenses but I haven't checked.