Can i Render a specific region in blender with specific resolution? For example, can I define a Render Region, but render it at the resolution I've specified in Output Properties?
You can simply use another camera.

Duplicate your camera, and keep it in the same place
Lower the Sensor size to &quot;crop&quot; the image
Use Shift X and Y to &quot;move around&quot;

Because you're not changing focal length, the lens distortion doesn't change.
It's as if you cropped the image in photoshop.