@Eva Seydl yes i'v followed this step, but i spoke with microsoft support, the original Windows 10 i'ts not good, you need a special version of windows 10, multissession or windows 10 for virtual desktop if you want prepare vhd on-prem and upload after.
I did differently :
- construct simple Azure VM with Windows 10 enterprise virtual destops preview 1903 (find in azure store)
- open VM + construc env + sysprep
- Stop VM
- find VHD in storage account (127 go) and download on hyper-v on prem