I have 30GB of MP4 video files that were shot with a GoPro helmet camera. The footage was taken vertically so it needs to by rotated -90 degrees. I can rotate an individual video file using some various tools i've found or Adobe Premiere. But there are 168 separate files and that would take some time.

So I'm wondering if there is any tool or feature in a program like premiere that would allow me to batch rotate all the video files keeping each video as a separate file.