Since the network adapter is off, no data can be received or sent.
However, if your device is:
If you manually put your computer to sleep via the Start Menu, does windows 11 download in sleep mode
Even then, the system decides when to connect – you can’t force a large download. Since the network adapter is off, no data
Even then, it will wake, download for a short period, then go back to sleep – not a sustained download mode. Since the network adapter is off