@Roger Roger Thank you for your patience over the matter.
No since the classic host pool are not ARM objects you won't be able to check the pool quota in Azure.You can use also the old Powershell cmdlets, but this isn't a GUI.
There is a management GUI that needs to be deployed manually, or you can use third party tools like from Sepago, Nerdio, Netapp to get GUI mode for WVD 2019 in Azure:
Deploy management tool with an Azure Resource Manager template - Azure | Microsoft Learn
Hope it helps!!!
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