Automated (but technical) method requiring use of python scripts: https://github.com/HardCorePawn/multibit_recovery
Manual method:
- Create offline version of https://iancoleman.github.io/bip39/
- Put in your MultiBit HD seed
- Set Derivation Path -> BIP32
- Set Client = "MultiBit HD"
- Copy all the address/private keys (click show more until you are sure you have more than all the addresses you ever used)
- Set Client = "Custom" -> Set Derivation Path = m/0'/1
- Copy all the change addresses/private keys (click show more until you are sure you have more than all the addresses you ever used)
Once you have all your private keys:
- In Electrum -> New/Restore -> Standard Wallet -> Create a new seed
- Once wallet is created, "Wallet -> Private Keys -> Sweep"
- Paste in all the private keys you got from automated or manual method
You should now have all your coins in an Electrum HD Wallet.
I made these screenshots of the iancoleman web page using the settings detailed by HCP. It's quite technical to use, so they might help.
If an address has had some, but not all of its Bitcoins sent out from multibit then the change gets sent to the list of addresses below. The screenshot shows the settings I used to recover those addresses.