It will probably be just for PC.
Though there were a couple of MMO's that tired to do both.
The problem with that though. Was the controls were serious issues. The game was also probably not successful. From a financial point of view.
So new MMO's may be afraid to try console. Not many console players seem interested in paying for a monthly sub. Parents may also not be interested in allowing junior to potentially spend billions for perks on a F2P console MMO either.
Though TES has been PC and xbox. So maybe it will try both.
At this point, all we can do is guess
