Can we define Bcc using Send-PnPMail cmdlet in PnP PowerShell?
As per the documentation and GitHub source code, defining BCC using
Send-PnPMail cmdlet is not supported.
Check below links form more information:
I have requested support for using BCC in PnP PowerShell and repository maintainers added it to the PnP PowerShell library.
This will be available with latest version of PnP PowerShell shortly.
Check this GitHub issue thread for more information: [FEATURE] Support for BCC in Send-PnPMail cmdlet