Not sure if my issues would be classified in the same category as yours, so apologies if I am wrong, but when I first played the games opening hour or 2, I noticed very brief random white outlines on characters, shadows looking like they had a rain effect on them and when I use a light on them (e.g a table under some stairs) the texture would pop in slowly in like 3 or 4 stages, plus other weird visual hiccups.
Before I went to play it again I used DLSS Swapper and update all the DLSS files (upscaler, frame gen etc) to the current latest version and never had an issue after that. I played in 32:9 5120x1440p, so not sure of it was an Ultrawide issue, a DLSS issue, or even both.