We will be using Video rotate + Flip video easy app on App Store to rotate multiple videos at a time on our iPhone/iPad. You can download this app from here.
- Import videos from Files App or Photo Library
- At first video will be displayed in default rotation angle, You can change this angle by applying rotation on the video by clicking on the direction arrows at the bottom.
- Click on Save Video to Library to save rotated videos into Photo Library.
- You can select whether you want to save videos with metadata or without metadata.
Download the app from this link.