I\'m currently using this template to create a vm by custom image. For the OS Disk part:
\"storageProfile\": {
\"osDisk\": {
\"name\": \"[concat(variab
If by different storage account
you mean a storage account in another subscription, then no. The storage account and virtual machine must be in the same subscription.
UPDATE
Found the answer in the template description page here: https://github.com/Azure/azure-quickstart-templates/tree/master/101-vm-from-user-image
Prerequisite - The Storage Account with the User Image VHD should already exist in the same resource group.
So based on this, as long as your storage accounts are in same Azure Subscriptions and are in same Resource Group, you should be fine even if the storage accounts are different.