Is the Sony FE 24-50mm F2.8 G Lens sharp? This page visually answers that question. Shown above are 100% crops from a lab-captured 28mm f/2.8 test image. Observe the contrast and resolution of these results.
Is the Sony FE 24-50mm F2.8 G Lens set to 28mm f/2.8 sharper than the Sigma 28-70mm F2.8 DG DN Contemporary Lens set to 28mm f/2.8? The image quality comparison above also answers that question. Switch between the results to see the sharpness differences between these lenses.