https://wccftech.com/skyrim-special-edition-nightingale-4k-mod/

The Frankly Skyrim Special Edition Nightingale 4K HD Armor and Weapons Mod offers scratch-made retextures of Nightingale weapons and armor with heavily enhanced normal maps.

The mod contains both 4K and 2K textures and uses vanilla texture maps that were upscaled with the use of neural network software. As can be seen in the screenshots below, the results of this technique are impressive for sure.