THIS WOULD NOT GIVE YOU AN EVENT BABY MOB, but a regular baby only

basically, will just allow us to breed event mobs but the baby will be normal, not an event mob or anything like this

you should be able to breed an event mob with a normal mob, or a spring mob with a halloween mob or whatever but the result will always be a normal mob

for example = halloween chicken + spring chicken = NORMAL chicken

either temperate, cold, warm, depending on the biome or the variant before the transformation, just like in vanilla