/gamerule mobchanging

A gamerule toggle for the changing mob event, aka things such as piglins/hoglins transforming into their respective zombified states when in the overworld. This can also be applied to the following:

zombies turning into drowned

creepers getting charged

skeleton traps (horses being struck with lightning)

Please note that those are purely examples, and there is probably a lot more that this gamerule could affect.