The official SqlServer module now includes a version of the Invoke-Sqlcmd cmdlet that runs in PSCore 6.2 and above. The version of the SqlServer module which contains this cmdlet is 21.1.18095-preview and is available in the PowerShell Gallery. In order to install this preview version of the module, you must run Install-Module (or Update-Module if you already have it installed) with the -AllowPrerelease. (Without that parameter you will receive the previous version of the module.)
Source : PowerShell Blog:
