Sony WX5 has a
12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor and features Bionz processor. On the other hand, Sony WX10 has a
16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor and features BIONZ processor.
Below you can see the WX5 and WX10 sensor size comparison.
Sony WX5 and Sony WX10 have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture. On the other hand, since Sony WX5 has 32% larger pixel area compared to Sony WX10, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.