I guess it would depend on if they have some really really powerful tools for the job, like there were some nifty tools used in the creation editor that helped make Open Cities in Bethesda games. Basically it takes the cities out of their own zone and plops them into the open world.
If they can move all of the coordinates and little details that are important but unseen then it's actually not that impossible, moving the terrain would only be hard if the game isn't to scale from a zone to zone. Although they would have to make invisible walls at the edge of their zones that don't connect to other zones or create A LOT of in between space.
Personally had suggested before that when you reach the edge of a zone into white space while flying instead of an invisible wall it phases you into a world map (at areas where the zone changes to another zone you just fly into the next one though), something like you would have seen in almost any major FF title - except 3d of course like what was in FFXI. So they don't have to develop the empty space until they want to, and you could fly out of Central Shroud right into Eastern Thanalan if you wanted. Curious if the ps4 could handle holding a 3d map in the background like that, like a more detail skyrim map (which ps4 can handle - I'm sure some fancy loading of the map near you could be done but yeah.. extra work).
Unfortunately I'm not sure all the time it would cost to ensure you didn't break every MSQ and other little details would be worth making the game zoneless, to the team I mean. Like I'd love to see it, but what would it add besides a really high level of immersion. People already accept zones.. So making it zoneless again would just be for the epeen in comparing to other mmos lol.
