Extending Copilot for Sales (standard)

I could not find documentation that would clearly state licenses needed when extending Copilot for Sales.

For example, if users have D365 sales enterprise license, can I extend Copilot for Sales with Copilot Studio by adding new topic that starts a flow and returns message to user in the Copilot for Sales side panel in D365?  Or does this require the separate Copilot for Sales license?