With some delay, my initial impressions on using PowerShell Core to perform administrative tasks against Office 365 has been published on the eNow blog. For those of you that have missed the news, PowerShell Core is a new flavor of PowerShell, stripped from the dependencies of most of the .NET framework. Instead, PowerShell Core is built on top of .Net Core and is designed to be cross-platform, lightweight and is distributed as open source.
Unsurprisingly, there are some issues with almost all of the modules used by Office 365, due to various dependencies on .NET binaries. A big issue is the fact that you cannot use any of the MFA-enabled modules, as the ADAL dialog is not supported on .NET Core. The same is true for anything based on Windows Forms, which means my favorite login script will also not work.
Even when you manage to connect, some of the modules will have issues, as they rely on other .NET functionalities to handle requests/output. For example, the AzureAD PowerShell module will not be able to parse the JSON responses for the Graph API calls, same is true for the Teams module and so on.
Only Exchange Online Remote PowerShell works flawlessly, and that’s hugely thanks to its architecture – being an actual remote session on to an Exchange Online Server, thus being agnostic to the device you are accessing it from. With the exception of support for MFA that is, which is of course very important.
Check out the full article here: http://www.enowsoftware.com/solutions-engine/powershell-core-is-ga-but-not-ready-for-office-365