@Lábaru Cantabro
Hi,
No I don't think it can be done.
Indeed, Windows will not allow you to enable auto-unlock on a fixed drive when the system partition is not encrypted (with BitLocker).
You could refer to the following official article as your reference:
https://learn.microsoft.com/en-us/powershell/module/bitlocker/enable-bitlockerautounlock?view=windowsserver2019-ps
After a user unlocks the operating system volume, BitLocker uses encrypted information stored in the registry and volume metadata to unlock any data volumes that use automatic unlocking.
Hope above information can help you.
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