Does the plugin work with videos?
Can video be used instead of the featured image?
Featured Images In RSS plugin outputs an image to the RSS feed. A video will not work as a featured image for a post or with the plugin.
Video in the body?
The plugin does not manage body content output. Body content output settings are managed from your WordPress site settings, either a summary or full content.
If videos are output from RSS body content to outside services, such as RSS readers or emails, the display of the video is controlled by the service, as well as the recipients email or browser settings.