I created a live course delivered via Zoom that featured a short illustrated PowerPoint using screen captures from Zoom. This allowed me to show the preparation and functioning of the Breakout Rooms feature. Then, if there was time and interest, the session would include a live practice with Breakout Rooms for the session participants.
The session would be followed up with individual coaching scheduled on a just-in-time basis before the negotiation or mediation session (and could include other internal or external participants).
To supplement the course, I created illustrated guides that reinforced the material covered in the course so that users could work independently with an increased sense of self-efficacy.