Well not quite an upload to Azure but you can easily use your existing VMDX files within Azure.
Today I was given a VMDX file form a supplier with the latest version of their virtual appliance, with a little bit of PowerShell magic you can quickly convert the VMDX into a VHD (don’t forget Azure does not support VHDX files!).
There’s various tools out there but I like the simplicity of the StarWind V2V converter (a free tool!). The tool allows you to easily convert your VMDK into a fixed VHD. Once converted you can use the Azure Storage Explorer (another great tool!) to upload the VHD.
It’s important to note however this method should only be used for single / one off conversions, if you have a VMWare estate you’re planning to migrate you should take a look at the Azure Migrate (another post on this soon).