In Veeam 12 it was possible to just type in an smb-path in the server field when exporting a backup as disk. It might not have been an official feature, but it worked.
in Veeam 13, the server field is locked and you can only select esxi/hyper-v servers.
Unfortunately it's not possible to bring this feature back due to security constraints. Please add the smb share as a file share and select it as a destination. Thank you!