How to fix frame jitter during Nioh 2 high VFX boss fights?

I was anxious when the screen shook violently during Boss VFX bursts, making precise parrying nearly impossible. I initially tried lowering the game resolution to reduce load; while FPS increased, CPU temperatures remained dangerously high per AIDA64. I used the GamePP Fan Curve Configuration Panel to force fan speeds to 95% at 75℃ and optimized the CPU voltage offset. CPU temperatures settled at 70-78℃ per AIDA64, fan speeds stabilized at 2300 RPM per HWiNFO64, and frame times improved to 14-19ms per RTSS.