I moved bitcoin from bitcoin-qt to armory in 2018.
I have bitcoin wallet.dat from the date of the transfer. It is empty.
and I have the armory paper wallet all the coins should be in
but it is only showing 1/3 of the coins when I import into electrum
A older backup is still good if your Bitcoin core wallet.dat is HD, that depends on the version of Bitcoin core that you've used.
If you open
a copy of that wallet.dat to Bitcoin core (
sync or not) and there's an "
HD" sign (
not slashed out) on the lower-right, it's an HD wallet.
For the Armory paper backup, it must be the "
Export key list" result.
Anyways, as explained by Bob, importing private keys to Electrum require a script type prefix if you want to derive SegWit address types,
if there none, it'll derive the legacy '1' address from the private keys.
Your '3' addresses however, I believe they won't be restored correctly even though you'll add
p2wpkh-p2sh: to the prv key to import them as '3' addresses.
You can try to import one of your '3' address' prv key (
compressed 'K' or 'L' prv key only) if it'll restore the correct address through the prefix above.
Does a change address start with a "3"?
It can be any address type, depends on the client or the settings.
Armory for example has a change address "
force a script type" setting.
BTW, you need the armory "
paper backup" not the "
key list"; or a digital backup of your wallet before deciding to sync Armory.
Because AFAIK, those '3' addresses can't be restored either through import private key option (
I haven't tested).