I believe the main differences are passenger density and on board amenities.I wonder what that really means, "not suitable for 'western' cruise markets." Are the rooms smaller? Casino? Lots of red paint and pictures of Xi?
What exactly could be different on an "eastern" cruise ship?
For example, in Asian markets guests are more likely to travel in multi-generational groups, meaning that connected guest cabins or suits are more likely to be incorporated into the design. Additionally, there is more focus on indoor amenities versus outdoor. Royal Caribbean for example differentiates the Spectrum of Seas which was specifically designed for the Chinese market to incorporate more indoor features while removing traditional outdoor features common in the rest of their fleet. Other examples include everything from choice of on board shows to the interior design color palettes.
It will be interesting to see how much Disney changes to bring it inline with the rest of the fleet. But given the ship is 75% complete, I don't know how much they will deviate from the overall original design in terms of number of cabins and signature features.