What about them? They wouldn't work for Skyrim.
Of course they would, both engines are capable of doing everything the Creation Engine can do. (and more)
No...it's not.
MMORPGs are made using engines that aren't demanding on system resources. That way, it appeals to as large an audience as possible. You look at ToR, WoW, and just about every other huge MMO on earth, and none of them have great graphics. That's so that just about anyone with a semi-decent computer can run it.
Warhammer Online uses Gamebryo
I'm not familiar with Chrome...but from what I understand, it's not developed or utilized enough to warrant using in such a huge title.
Sniper Ghost Warrior used Chrome and the game looks almost as good as Crysis 2.
Wouldn't be surprised if an Asian MMO used it, they like to look pretty. Aion used CryEngine 1.
There is more than one MMO using CryEngine (all three of them)
Aion
Entropia Universe
ASTA
ArcheAge
Warface
Mechwarrior Online