Get all Azure Public IPs from all subscriptions that the current in user has access to.

Azure_Get-AzPublicIpAddress_All_Subscriptions.ps1

$now = Get-Date -UFormat "%Y-%m-%d_%H-%M-%S"
$filepath = 'C:\temp\Azure_PIP_export_' + $now + '.csv' 
$subs = Get-AzSubscription

foreach ($sub in $subs) {
    Select-AzSubscription -Subscription $sub.Name
        Get-AzPublicIpAddress `
        | Select-Object -Property Name, ResourceGroupName, IpAddress, `
        @{label='FQDN';expression={$_.DnsSettings.Fqdn}}, `
        @{label='ID';expression={$_.IPConfiguration.ID}} `
        | Export-Csv -Path $filepath -NoTypeInformation -Append
}