I think it should work, haven't seen any black bars in ESO so far. Depending on your current screen and graphics card you might even be able to override the standard resolutions and get your graphics card to provide that resolution as a valid choice (whether your screen displays it is a different question).
I've done the same and it worked when trying 2560x1440 on my old 1920x1200 screen with a Nvidia card.
Besides that, if you're really up to spending that much money on a new screen, I'd grab a Asus ROG 27" with 144 Hz and 3D support. It's not as wide, but I guess it should be higher, possibly providing you an even better view (and 3D works rather well with ESO).