When this plugin is enabled, MusicBee will only play the starting portion and optionally the ending portion of a track. You can set a start offset and duration in the Plugin preferences screen and optionally an offset from the track end/ duration (all in seconds)

To activate, right click in the Now Playing panel/ Preview Mode/...
Enable Track Preview Mode - this needs to be done on each restart of musicbee.
Suspend Track Preview Mode - if you want to keep listening to the current playing track. The preview mode when the current track finishes
or assign and use these hotkey commands:
Player: Toggle Track Preview Mode
Player: Suspend Track Preview Mode
unzip and put in the plugins folder:
https://getmusicbee.com/download/plugins/mb_TrackPreviewer.zip