Yes, it is possible.
https://learn.microsoft.com/en-us/azure/virtual-machines/windows/capture-image-resource
You have same methods available in Azure VMs like traditional VMs.
Sysprep Support for Server Roles
UILanguage settings in answer files.
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Is it possible to use an unattend.xml with SysPrep on an Azure VM, to configure all language, region and system UI default language to en-GB?
Yes, it is possible.
https://learn.microsoft.com/en-us/azure/virtual-machines/windows/capture-image-resource
You have same methods available in Azure VMs like traditional VMs.
Sysprep Support for Server Roles
UILanguage settings in answer files.