I'm having a lot more fun with the Oblivion remaster than I did with the original game (which I first played years after Skyrim came out).
But I will say, while the graphics are better than the original Oblivion, Unreal 5 is NOT an improvement over the engine they used for Skyrim, not from a visual point of view, at least not for me. Quite frankly, I'd much rather have Skyrim-era graphics, which are plenty good enough, and Skyrim's quick startup times, than have to wait for shaders to load as you do with lots of recent games.
The shaders do their thing the first time you launch oblivion, and then not again. Stalker had an issue where it would recompile the shaders of you changed a setting, not sure if they fixed that.
Skyrim does load fast, though, even on switch. Which wouldn't need to compile shaders anyhow.
Yeah, shaders aren't the problem with Oblivion; the problem with Oblivion is that when you move to a new scene everything looks like it's made of enormous triangular things until the rendering catches up, which on my machine can take five seconds or so.
If this is typical for Unreal 5 it's what I'd call a deprovement (rather than an improvement).
I get something similar to the artifacts you mention; i think the fix is to delay actually drawing the world until it's truly finished loading, but i'm no AAA game company.
Either way, something about the remaster makes me fatigued playing it. I might try turning off all AI and motion blur and go for higher FPS and see if that helps. It isn't the only game that does this to me, but i find with games from the 8 and 16 bit era (as a comparison), they load so fast and close so fast that the second tedium sets in at all i can just quit; the newer games there's already a time investment just to get to "in control of a character", at least for me, on PC.
The thing that fatigues me with the Oblivion remaster are the constant loading screens. Go from the first floor to the second floor of a house? Loading screen! Some are faster than others, but they all break the flow.
But IIRC this was a problem with the original too, not something I can blame on Unreal 5. :-)
But I will say, while the graphics are better than the original Oblivion, Unreal 5 is NOT an improvement over the engine they used for Skyrim, not from a visual point of view, at least not for me. Quite frankly, I'd much rather have Skyrim-era graphics, which are plenty good enough, and Skyrim's quick startup times, than have to wait for shaders to load as you do with lots of recent games.