YouTube channel ElAnalistaDeBits posted a nearly 20-minute video comparing the PlayStation 5 and Xbox Series versions of Kingdom Come: Deliverance 2. The developers sent out preview copies of the game, which made it possible to create such a video.
Xbox:
Quality mode: 2160p/30fps with FSR upscaling to 1440p.
Performance Mode: 1440p/60fps upscaled to 1080p with FSR (60+ fps with VRR).
PS5:
Quality mode: 2160p/30fps with FSR upscaling to 1440p.
Performance Mode: 1440p/60fps upscaled to 1080p with FSR (+60fps with VRR).
PS5 Pro:
2160p/60fps resolution with dynamic 1440p resolution with PSSR (60+ fps with VRR).
As expected, the PS5 Pro version performed best.