Modder xoxor4d recently presented his RTX remaster of Grand Theft Auto IV mod-addon. It aims to add PBR materials (with physically correct rendering) to all textures, which further improves the quality of the graphics:
Update 1.1.8 has also been released for the RTX remaster of GTA VI. xoxor4d has fixed the issue with blurry images on the main character's phone screen, and has also published several screenshots for comparison (fog effect):
xoxor4d distributes the project "gta4-rtx (GTAIV RTX Remix Compatibility Mod)" via GitHub.