When creating a rectangle in Sketch and using an image as a background fill with the 'fill' setting it automatically crops the image in the center if it is not the same aspect ratio of the rectangle. Is there a way to adjust the background fill location so that a different part of the image is seen?
The image fill option is designed for repeating patterns, therefore, there is no way to adjust the crop. If you want to use a certain part of an image as a background, you're better off using image masks.
To mask two layers, make sure the photo is on top of your shape or object you want to mask with. Select both, and right click to select