You can add a wallet from a private key, and scan an HD wallet xprov key instead of just a private key. That will allow you to add more than one HD account. But, honestly, if you want to stay safe, just shell out $15 to $30 for a Ledger hardware wallet and use that instead. Or if you have a Samsung phone, buy a Ledger Trustlet app on the Play Store, which will let you use your phone as a hardware device.

Also https://news.wallet.mycelium.com/update-for-december-more-bitcoin-buying-choices/