Assign PEX ranks to world

Hey all!

I have been trying to figure out how to assign ranks to a single world. For example, I only want the skyblock ranks to be added as a prefix ( [Skyblockrank] ) in the designated skyblock world. I believe there is a way to do this but I'm not sure how to and can't find it anywhere on the internet.
If anyone could help me out I would be really happy!

Thanks,
NocturneNetworkOfficial