Spending BTC from an Electrum watch-only paper wallet? I've an old BIP-38 paper wallet, and I imported that address into an Electrum (version 3.3.6) watch-only wallet. 

I now want to transfer that BTC to an Exchange. I have the relevant password for the Electrum wallet and private key for the paper wallet and I've checked on a block explorer that the balance at that address is correct and it is.

Question: How do I spend from that Electrum watch-only wallet? 

If I open Electum I'm only given an Export option (and from there select amount, select fee, preview, copy display where I end up with a type of report on amount sent, size of transaction, fee, locktime, inputs and outputs

I followed this option, but nothing is happening. Btc is still at my address and not at the Exchange's address and its been a while and the fee was set to max. 

Where to from here? Any advice? 

(PS: I see advice here to sweep the paper wallet address into the Electum wallet but I understand that would incur a transaction fee, and seeings that I'm going to send that BTC to an Exchange and that transaction would also cost fees - so I don't want to go that route :) ) 

ty
As you know, it isn't possible to spend money using a wallet that doesn't contain the relevant private-key. Your watch-only wallet cannot be used for spending.
See https://bitcoinelectrum.com/importing-your-private-keys-into-electrum/
In brief it says

These instructions are for Electrum 3.0 and later.
You cannot import private keys into an existing HD wallet.
Start new electrum wallet file
Click on next to see the wallet type selection window:
select “Import bitcoin addresses or private keys”.
Enter one private key per line. Electrum supports mini private keys and full sized keys in Wallet Import Format (WIF).

You may need to convert your BIP-38 data into WIF first.
It is worth reading their notes on why you might prefer sweeping to importing despite the transaction fees involved.