Finding a list of users who don't have an exchange license

One example:

Using on-prem Exch PS:

$list = Get-Mailbox  -resultsize unlimited | ?{$_.OrganizationalUnit -notmatch 'Contractors'}

 $list.userprincipalname > list.txt

Then using Ex Online PS:

$list = gc .\list.txt

foreach ($id in $list) {get-msoluser -UserPrincipalName $id | ?{$_.IsLicensed -eq $false }}

That will give you a list of users not licensed.

Manipulate or change search as you see fit.