You want to do the same encryption method as Krux, right? It exports encrypted backups as a QR Code with your password. But only in mnemonic format.
Anyway, if you want to do this with a native Bitcoin Core wallet, you'll have to do it manually through third-party applications.
Or, since it's cold storage for 10+ years, that I won't spend unless there is a good reason to do so, I could just stick with BIP38 which does that already. The problem is that I will need to have single addresses that aren't anyhow connected and that they'll be legacy addresses which means higher fees when I spend.
Now to my original question, does everyone who uses Core, still keep their
wallet.dat in digital media?