Get a list of Zones available in a given Azure Region

Get-AzRegionZone.ps1

param(
  [string]$Location,
  [string]$SubcriptionName
)
$subObj = Get-AzSubscription -SubscriptionName $SubscriptionName
Set-AzContext -SubscriptionObject $subObj

$payload = @{
    location        = $location
    subscriptionIds = @("subscriptions/$($subObj.Id)")
} | ConvertTo-Json
$result = Invoke-AzRestMethod -ResourceProviderName 'Microsoft.Resources' -ResourceType checkZonePeers -ApiVersion 2020-01-01 -Method POST -Payload $payload
$zones = ($result.Content | ConvertFrom-Json).availabilityZonePeers.availabilityZone
return $zones