Short answer
Coaching playlists hold complete or clipped call recordings for training. HubSpot's KB says any user can create a playlist or folder, people a playlist is shared with can add recordings, and followers get a daily email when new recordings are added. It needs Sales Hub or Service Hub Professional or Enterprise.
1. The tool
My demo portal has no playlists yet.

2. What to include
- Calls that handled a common objection well.
- Discovery calls on a new product.