Benefits
Cross-Team Velocity Chart displays advanced aggregated velocity analytics of completed and active sprints for several Scrum boards and, therefore, several teams.
Cross-Team Velocity Chart answers the following questions:
What is the productivity trend for a set of teams?
How does a set of teams deliver on its sprint commitment?
To what extent sprint’s scope is subject to change?
This chart type only makes sense when all teams have aligned their estimations. That means that one story point is the same across all teams to be analyzed on this chart.
Getting started
Track velocity across several teams article gives the essential information on how to configure and read Cross-Team Velocity Chart.
Refer How to install app and gadgets article if you don’t know how to add the gadget.
Best practices
However, the articles below use Team Velocity Chart for the explanation, concepts and configuration are common for all types of velocity charts, including Cross-Team Velocity Chart:
Setting up your Cross-Team Velocity Chart
https://brokenbuild.atlassian.net/wiki/spaces/~503243278/pages/3130753025/Chart+configuration#Cross-Team-Velocity-Chart-configuration explains the chart configuration, particularly each setting.