Tested on vCenter 7.0.3 22837322

# save as .ps1 and run in PowerShell I have put in bold what you need to change
# import script

function Replace-SpecialChars {
    param($InputString)
    $SpecialChars = '[#?\/{:}]'
    $Replacement  = '-'
    $InputString -replace $SpecialChars,$Replacement
}

function ExportAlarm() {
   if( -not (Test-Path -Path $exportFolder -PathType Container) ) {
      mkdir -Path $exportFolder}
 Connect-VIServer $serverToExportFrom -User 'administrator@vsphere.local' -Password 'VMware1!'
 # Exclude vCenter specific Alarms containing "Exhaustion"in the name AND matching the filter
   $alarmToExport = Get-AlarmDefinition $alarmToExportName | ? {$_.name -notmatch "Exhaustion"}
   $alarmToExport | % {
      $a = Get-View -Id $_.Id
      $CustomAlarmName = $alarmprefix + ' ' + (Replace-SpecialChars -InputString $a.info.Name)
     $a.info.Name = $CustomAlarmName
     $ShortCustomAlarmName=$CustomAlarmName[1..84] -join ''
     $a.Info | Export-Clixml -Path ($exportFolder + $ShortCustomAlarmName  + ".xml") -Depth ( [System.Int32]::MaxValue )}
  }
 $serverToExportFrom = "172.168.1.5"
 $alarmToExportName = "172-168-1-5alarms"
 $exportFolder = "C:\temp\"
 $alarmToExportName = "*"
 ExportAlarm
 Disconnect-VIServer * -Confirm:$False -Force:$True

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# save as .ps1 and run in PowerShell I have put in bold what you need to change
#export script

function ImportAlarm {
 Connect-VIServer $serverToImportTo -User 'administrator@vsphere.local'-Password 'VMware1!'

# Remove all but vCenter-specific Alarms from the target vCenter and wait for 15 seconds before we bulk-import the new Alarms
 Get-AlarmDefinition | ? {$_.name -notmatch "Exhaustion"} |Remove-AlarmDefinition -Confirm:$false
 sleep 15

 Get-ChildItem -Path ($exportFolder + "*.xml") | % {
 $deserializedAlarmInfo = Import-Clixml -Path $_.FullName
  # We need to limit the Alarm-name to 80 characters for it to import correctly
  $deserializedAlarmInfo.Name = ($deserializedAlarmInfo.Name[0..76] -join "")
  $deserializedAlarmInfo.Description = ($deserializedAlarmInfo.Description[0..254] -join "")
  $importedAlarmInfo = ConvertFromDeserialized( $deserializedAlarmInfo )
  $entity = Get-Folder -NoRecursion 
  $alarmManager = Get-View -Id 'AlarmManager-AlarmManager'
  $alarmManager.CreateAlarm($entity.Id, $importedAlarmInfo)}
 }
 # This function converts a Powershell object deserialized from xml (with Import-Clixml) to its original type (that has been previously serialized with Export-Clixml)
 function ConvertFromDeserialized {
 param($deserializedObject)
 if($deserializedObject -eq $null){return $null}
 $deserializedTypeName = ($deserializedObject | Get-Member -Force | where { $_.Name -eq "psbase" } ).TypeName;
 if($deserializedTypeName.StartsWith("Deserialized.")) {
   $originalTypeName = $deserializedTypeName.Replace("Deserialized.", "")
   $result = New-Object -TypeName $originalTypeName
   $resultType = $result.GetType()
 if($resultType.IsEnum){
      $result = [Enum]::Parse($resultType, $deserializedObject, $true)
      return $result}
 $deserializedObject | Get-Member | % {
# exclude "SystemName" entries from the XML-import as these will fail during the CreateAlarm call
   if($_.MemberType -eq "Property" -and $_.Name -ne "SystemName") {
     $resultProperty = $resultType.GetProperty($_.Name)
     if($resultProperty.CanWrite ){
        $propertyValue = ( Invoke-Expression ('$deserializedObject.' + $_.Name) | % { ConvertFromDeserialized( $_ ) } )
        if($propertyValue -and $resultProperty.PropertyType.IsArray ) {
           if($propertyValue.GetType().IsArray){
              $elementTypeName = $resultProperty.PropertyType.AssemblyQualifiedName.Replace("[]", "")
              $elementType = [System.Type]::GetType($elementTypeName)
              $array = [System.Array]::CreateInstance($elementType, $propertyValue.Count)
              for($i = 0; $i -lt $array.Length; $i++){
                  $array[$i] = $propertyValue[$i]}
                  $propertyValue = $array
              } else {
                  $elementTypeName = $resultProperty.PropertyType.AssemblyQualifiedName.Replace("[]", "")
                  $elementType = [System.Type]::GetType($elementTypeName)
                  $array = [System.Array]::CreateInstance($elementType, 1)
                  $array[0] = $propertyValue
                  $propertyValue = $array}}
           $resultProperty.SetValue($result, $propertyValue, $null)}}}
     } else {
       $result = $deserializedObject}  
 return $result     
 }
 $serverToImportTo = "172.168.1.5"
 $exportFolder = "C:\temp\"
 ImportAlarm
 Disconnect-VIServer * -Confirm:$false -Force:$true

By Kader