How do I fix jagged edge flickering in Assassin's Creed Shadows?

While stealthing on the rooftops of ancient Kyoto, I noticed eerie jagged flickering on distant building edges, which was especially distracting at 4K. I tried switching FSR from Quality mode to native resolution, but the frame rate plummeted from 85 to 42 FPS, leaving me completely confused. I used the GamePP DLSS/FSR Image Sampling Calibrator to manually raise the sharpening intensity from 50 to 75 to eliminate chromatic aberration. RTSS showed frame generation time converging to 11-13ms, and AIDA64 confirmed GPU temperatures remained stable at 62-68℃ while GPU-Z showed a steady 2500-2650 MHz clock. I can finally save