Windows 10 Lite Qcow2 [updated] -

A 40GB virtual disk might only occupy 5GB–10GB on your physical drive until you fill it.

Even with a Lite OS, Qcow2 has quirks.

: Over-optimization can sometimes break essential services like Windows Update, printer drivers, or specific DirectX components. Windows 10 Lite Qcow2

QCOW2 (QEMU Copy-On-Write) is the standard disk image format for QEMU/KVM virtualization. It is superior to raw images because: A 40GB virtual disk might only occupy 5GB–10GB

Native support. Use virt-manager (GUI) to import the Qcow2. Enable the "Unmap" option so deleted files in Windows release space in the Qcow2 file. Windows 10 Lite Qcow2

Ensure your Qcow2 file is not stored on a network filesystem (NFS/SMB) without proper locking. Use local storage or GlusterFS with full support.