One would need to define what is meant by "significantly different" as well as the exact purpose of the hash functions. i.e. I suggest not to start with the im

One would need to define what is meant by "significantly different" as well as the exact purpose of the hash functions. i.e. I suggest not to start with the implementation but with what is trying to be achieved. Putting the cart before the horse, so to speak, is a recipe for creating bad crypto.