Sending money to a friend should be entered as transaction type "[Out] gift" or "[Out] donation" (see: Explanation of Transaction Types). If you receive money, it should be the transaction type "[In] gift/tip".
Alternatively you can enter the pair "[Out] Spend" for outgoing / lending and "[In] Income" for incoming / repayment, however these transaction types might be treated differently for tax purposes.
This will correctly reduce the purchase pool and trigger a gains/loss calculation in the giving account and establish the coin with the cost base of the time of transfer in the receiving account.
In the tax report you will find income / gift in the income report and the gift/donation in the donation report, each time with the value of transfer.
If you would like to keep the transaction out of the tax report completely, you can use one of the new transaction types - "Income (non taxable)" and "Expense (non taxable)".
Please be aware that excluding income from the tax report and sending crypto currencies away without a capital gains calculation for the difference between receiving and sending the coin (as expense non taxable will do) might not be legal for the tax laws of your country. Please check with a tax advisor or the financial authority first.