I've had a presentation for a promising new sandbox MMO called Pax Dei.
It looks like an Arthurian fairytale. I saw characters in flowing dresses in a sun-dappled wood working together to build picturesque hamlets or settlements. They placed down floors and walls in a blueprint-style way, as in other building games, before equipping plate armour and weaponry and venturing to darker, more barren and dangerous areas of the world. The smoky spirit-like enemies they encountered there were genuinely scary.
One of the most eye-catching things about Pax Dei is its looks. This is Unreal Engine 5 and Pax Dei is a handsome beast, and you can see some of that in the screenshots here, although I think they're pulled from the announcement trailer. But in play, it looks similar, and the settlements you create are gorgeous.