Photos taken with a mobile phone or digital camera contain metadata in the image file. One of the types of metadata is photo orientation. How the orientation is recorded and how the orientation are displayed can vary based on the device taking the image and the software or website displaying the image. This can cause the photo orientation to display differently between Eagle, your website and other portals.
How to avoid sideways images
The most common scenario for sideways photos is when the photo was taken on a smart phone in portrait orientation. It will also vary on the type and version of smart phone as to how the metadata is recorded. If you are continually getting sideways images, the best way to avoid them is trial and error to determine which device is causing the issue, then avoid using that device if possible. If you don't have another device, you can follow the below steps to overwrite the metadata and fix any images that are appearing sideways.
How to fix images that are sideways
Follow the below steps to reset/overwrite the image orientation:
Open the image in Paint (or any other image editing software)
If the image's orientation appears correct, press CTRL + S to save it, then overwrite the existing file
If the image is sideways, rotate the image so it appears correctly, press CTRL + S to save it, then overwrite the existing file
Go back to the listing in Eagle and re-upload the image