iOS App Submission screenshot requirements

the must screen size requirements are for 6.5, 5.5 and 12.9 inches.
 which are the ones below,


6.5 inch (iPhone XS Max, iPhone XR)
1242 x 2688 pixels (portrait)

2688 x 1242 pixels (landscape)
Optional
Upload 6.5-inch screenshots

5.5 inch (iPhone 6s Plus, iPhone 7 Plus, iPhone 8 Plus)
1242 x 2208 pixels (portrait)

2208 x 1242 pixels (landscape)
Required if app runs on iPhone
Upload 5.5-inch screenshots

12.9 inch (iPad Pro (3rd generation))
2048 x 2732 pixels (portrait)

2732 x 2048 pixels (landscape)
Optional
Upload 12.9-inch iPad Pro (3rd generation) screenshots

references:
https://help.apple.com/app-store-connect/#/devd274dd925