Is there any way to add an existing o365 Tenant Cloud group as System Admin to all Sites on our o365 SPO Tenant via power shell?   I know we can do it with accounts.  But apparently since o365 Tenant cloud groups have no email it's not possible via script.  What's up with that?  The only way we can is creating a permission group on each site and we are not looking to do that.

i dnt think powershell is supported in o365 you can check below links for multitenant reference:

http://blogs.technet.com/b/educloud/archive/2013/08/02/multi-forest-and-multi-tenant-scenarios-with-office-365.aspx

https://support.office.microsoft.com/en-us/article/Manage-administrators-for-a-site-collection-9a7e46f9-3fc4-4297-955a-82cb292a5be0?CorrelationId=1e739175-9b37-45eb-8c7c-7f6d18dac66d&ui=en-US&rs=en-US&ad=US

http://nikpatel.net/2014/06/03/best-practices-for-configuring-sharepoint-online-tenant-part-ii-configuring-sharepoint-administrative-accounts-for-sharepoint-online/

--------------------------------------------------------------------------------------------------------------------------------------

Please mark answer as correct if it is correct else vote for it if you find it useful Happy SharePointing