I'm sorry if i sound like a newbie, however, my wallet is Electrum v2.8.3 (non HD). And to kill any doubt, i've just uninstalled it and deleted all data from Roaming directory, including wallet.dat. Then i reinstalled it, and started from scratch, and did exactly as in the images (looks like Electrum non-HD version does support "Import" as a matter of fact), but still, when i added the Private Key, it shows me this address "1Emhxm5Fx1cZCKRfrxTSFCEuBN7mZjMtQD" as opposed to my address that starts with "1Fy8dvuHjiTL........". Blockchain.info shows that the Private key belongs to "1Fy8dvuHjiTL....." and NOT "1Emhxm5Fx1cZCKRfrxTSFCEuBN7mZjMtQD", so i guess there is some kind of bug on Blockchain.info for showing me a PK that belongs to this empty address instead.
OP seems to not understand the difference between "Sweep" and "Import"
"Sweeping" creates a transaction that sends the coins from that address to your new Electrum (or any other) address that you choose... thus, it will have a different private key and different address.
The only way to maintain the same private key and address is to "import" the key... and this is not possible into an Electrum HD (aka "seed based") wallet... you can only "import" into an Electrum wallet that you specify as being based on public/private keys when you create it:
"File -> New/Restore"... give it a name... select "Standard Wallet"... then you should see this:
DO NOT select "create a new seed"... instead, make sure you select
"Use public or private keys", click "next". Then put your private key into the box on the next screen and click "next".
Your wallet will be created with your "old address" and transaction history and balance for that address.
NOTE: It is NOT recommended to import, as this new wallet is NOT an HD wallet and so it is not backed up by a 12 word seed phrase. You must therefore make regular backups of the wallet file and/or private keys so that you are able to recover your coins if your computer blows up or your hard drive dies etc.
Sweeping is a much better option!!