Without getting into the tech really deep, some of which I don't understand, no, it's not possible. There are 3rd party attempts at 3D clients for UO for free shards, but the official UO? No. The 3D client was discontinued 5 years ago. Many things client-side have been rewritten since then, and so there are all kinds of technical/system hurdles involved due to incompatibility.
I have to admit, I wish that when they killed off KR, they had brought back the 3D client and updated it. If the 3D client had been a lot better supported over the last 10 years, it would be very nice, especially in regards to resolution. I was reading about Elder Scrolls Online, and how many of the people in charge of UO when the Third Dawn client came out all left to go with Richard Garriott to his new company, and some may have been laid off as well or left to go elsewhere. That was the start of UO's client problems. Release a brand new client, then lose a bunch of the people who were driving it, bringing in a completely new group of people.
The EC engine does support 3D, and I hope someday we see it in the game.