Samsung NX2000 has a 20.0MP APS-C (23.5 x 15.7 mm ) sized CMOS sensor . On the other hand, Nikon D5600 has a 24.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor and features Expeed 4 processor.
One other difference between these two cameras that is worth mentioning is that Nikon D5600's sensor doesn't have an anti-alias (Low-Pass) filter. Removing anti-alias filter increases the sharpness and level of detail but at the same time, it increases the chance of moire occurring in certain scenes.
Below you can see the NX2000 and D5600 sensor size comparison.
Samsung NX2000 and Nikon D5600 have almost the same sensor size so none of them has any significant advantage over other in providing control over depth of field when used with same focal length and aperture.
DxOMark Sensor Scores
DxOMark is a benchmark that scientifically assesses image quality of camera sensors. It scores camera sensors for color depth (DXO Portrait), dynamic range (DXO Landscape) and low-light sensitivity (DXO Sports), and also gives them an overall score. Samsung NX2000 and Nikon D5600 sensors have been tested by DxO and the results show that D5600 has a better overall score of 84, 9 points higher compared to NX2000's score of 75.