Is there a way to set default values youtube video duration, favourites, likes, views, etc. in bulk?

Instead of managing your videos individually, you can use the integrated CSV import/export/update addon. Here is what you need to do:

1. Export all videos to a google spreadsheet(recommended)
2. Modify the video information there and import them back in using the update option

By this way;

• You will have an external backup.
• Every video will be bulk updated with the new information without editing each one of them.