RuneScape/Gielinor in Unreal Engine

Sorry for the very long reply, I’ve been busy the last days reading books about C# and C++.
I am going for RS3.

I am planning to make a game where RS3, World of Warcraft, and Minecraft are combined.
But, My first plan is to make the runescape map first and add another world for world of warcraft which will be made after RS3 map.