SamsungGalaxy Smartphone with the OneUI 2.0 and Android 10 OS update has the new smart cropping feature. To try it out, just take a screenshot on your device, then tap on the button for cropping and editing from the menu overlay that appears on the bottom.
In editing mode, it will automatically detect the picture in the screenshot and highlight its approximate borders. Now you can adjust the size by dragging your finger around the border.
After that just tap on the blue crop button on the upper-right, and then tap on “Save” in the upper-right to save the image to your gallery.