When exporting from Electrum, unfortunately, only the following columns are visible, but no relevant inputs and outputs, which are needed for taxes in case the tax software cannot fetch them by itself. I have written an open-source program that generates a CSV file for Bitcoin transactions, which also displays the relevant inputs and outputs. I also provided examples in the README file, which illustrate how the CSV will look like. See https://github.com/iiinnniii/bitcoin-csv-generator.

transaction_hash
label
confirmations
value
fiat_value
fee
fiat_fee
timestamp