Hi, I'm John, the developer of Resolution File Manager, a free Windows app for browsing, organising and converting collections of photos and videos.

It scans folders and subfolders and combines image/video previews with sorting and filters for resolution, codec, file size, duration, frame rate and bitrate. It also has tags, ratings and batch renaming.

The workflow I use most is with my movie collection:

1. Scan the collection, including the separate subfolders, and sort by resolution.
2. Select any 4K films I would prefer to keep at 1080p and convert the selected group to 1080p.
3. Compare file size with running time to find unusually large movies, then convert suitable selections to H.265. I often use around CRF 25 as a starting point, check the output and adjust to taste before removing originals. Savings and quality depend on the source and settings.

I've tested it on a 6 TB shared drive containing thousands of videos and images.

It's free to use, with an optional coffee donation. Microsoft Store listing:
https://apps.microsoft.com/detail/9NZL6GF5JSJK

Happy to answer questions about the app and how this workflow works.