Send-MailMessage : Cannot convert 'System.Object[]' to the type 'System.String' required by parameter 'Body'. Specified method is not supported.
My bad i did'tn check the variable type used by -Body parameter...
Replace the Send mail part by this one, it should work (but not tested)
# Send email
$MailBody = ConvertTo-HTML @params | Out-String
$ReportingMail = "esx@lab.local"
Send-MailMessage -To $Email -From $ReportingMail -Subject $MailSubject -BodyAsHtml -Body $MailBody -SmtpServer $SMTPServer