[pvg]

You get a recovery key when the original key is generated.

[floatingatoll]

Yes: You can export a FileVault recovery key when enabling FileVault, whether on a T2 Mac or not.

No: There’s no opportunity to use FileVault recovery keys when you’re doing a DFU on a T2 Mac. If you have to DFU, your data is lost.

(edited to clarify per reply)

[pvg]

That wasn't the question I was answering or was asked, I think.