Is there a way to configure Azure Activity logs to be forwarded to a Log Analytics instance using PowerShell? Essentially the same that can be performed using the Portal as
You may use the PowerShell cmdlet New-AzureRmOperationalInsightsAzureActivityLogDataSource.
Illustration:
New-AzureRmOperationalInsightsAzureActivityLogDataSource -ResourceGroupName <LogAnalyticsOMSWorkspaceResourceGroupName> -WorkspaceName <LogAnalyticsOMSWorkspaceName> -Name <NameOfThisOperationalInsightsAzureActivityLogDataSource> -SubscriptionId <SubscriptionId>
For more information refer https://docs.microsoft.com/en-us/powershell/module/azurerm.operationalinsights/New-AzureRmOperationalInsightsAzureActivityLogDataSource?view=azurermps-6.13.0
Hope this helps!!