copy & paste
Copy & paste the same artboard style (with exactly the same items on it) to another artboard. Also copy & paste the same item with the same position to another artboard (cmd + alt + shift + v) as in InDesign.
If you select an artboard, copy and paste it, another artboard will be created with all the same contents.
If you copy an item from one artboard and copy it to another, the location of the item should match where it was copied from.
This is in our current update of XD as of this writing.
Igor Milenković commented
Is this really completed feature? What about overlay type? When I tried to copy few artboards, transition type was copied but not overlays.