I want to know the steps of how to make a really good MMORPG map.
Have a look at worldmachine, sketch your ideas out first.
Look at games you like, how they did it.
Start small scoped and extend the playable zone, or it will be never finished.
My thoughts were that World Machine worlds generate maps that have too much variation, but I guess there would just be some adjustments needed. Dexter, the answer to your question depends entirely on what type of MMORPG game you are going for, World Machine will take care of the heightmap, and maybe help with texturing, but you still need to place foliage, objects, and everything else. There is no guide on how to make a good MMORPG map, because let’s face it, it is a HUGE task.
I think that world machine will be fine but it says on their website that theres a paid version and a free version (I guess I will work with the free one because the paid one costs a lot) and before I downloaded the free version, it says on the fined print “You may not use the results of the Basic Edition commercially. Resulting heightfields and textures may not be used in a commercial project, nor integrated into for-sale artwork.” does that mean I can’t sell my game when I’m finished? It also says, “The maximum resolution output from the Basic Edition is limited to 513x513 pixels.” will that be good enough resolution for a game?
Thanks 
You will need the paid version for what you are trying to accomplish. You will not be able to sell your game using the free version of WM. As for the resolution, I’d say that you’ll need at least a resolution of 80,000*80,000 if your map were to be 20kmx20km for it to look good.
Ok thank you so much for clearing that up. Looks like I have to save up then
Is there another option to make a map? preferably free.
Of course, you could do it manually (so just with the landscape tool in the UE4) or use terresculptor or generate your heightmap in gimp/blender
There are many ways of making maps. You can build it in Blender, or in Unreal Engine with landscape tools.
I would recommend against “heightmap” based landscape generators; they are great for screenshots and for flight simulators, but they typically don’t play very well for ground-based games. Maps that play well tend to not look as good from the 10,000 meter view that most heightfield generators use.
ok thanks