Big-B 4.6 USD? Where did you got this from?
Receiving money (USD -> EUR): (which was the point of this conversation, wasn't it?)
1. Receiving money to your USD bank details doesn't cost anything, so when you receive 10 USD you get 10 USD to your TransferWise account.
2. Then you have to convert it to EUR, this costs 0.04 USD for 10 USD.
3. In the last step you want to get the money to your bank account. TransferWise has a fixed 0.63 EUR fee for withdrawing money (SEPA Instant, so it arrives instantly), so even if you withdraw 10,000 EUR you still only have to pay 0.63 EUR.
For up to 500 EUR you can also just add your TransferWise debit card to your bunq account and withdraw the money that way, for Premium users bunq doesn't ask for any fees up to 500 EUR and paying in EUR is free with the TransferWise card (Click on one of your bunq accounts -> Add money).
TOTAL FEE: 0.66 EUR for receiving 10 USD to your bunq account.
Sending money from bunq (EUR -> USD):
Even with a TransferWise account you can still use the bunq integration, your (non-Euro) contacts are synced between bunq and TransferWise. Sending 10 USD costs 1.10 EUR or 1.22 USD
As mentioned several times, both support SEPA Instant. So if you want to use the TransferWise website to send money, just select the cheapest option to add the money for a transfer. It will be a normal bank transfer, but because both support SEPA Inst it is basically as fast as the other options.
TOTAL FEE: 1.22 USD for sending 10 USD and 1.59 USD for sending 100 USD, with the real (no Mastercard) exchange rate
Sending money from your USD account at TransferWise
Let's say you received USD on your TransferWise account and you want to send it to another person/company in USD, so you don't need to convert it to EUR first.
There is a fixed fee for sending USD from your TransferWise balance, and it is always 1.40 USD. Which is expensive for 10 USD, but keep in mind, even for sending 10,000 USD from your USD balance it still only costs you 1.40 USD.
TOTAL FEE: 1.40 USD for sending any amount (10 USD or 10,000 USD, it doesn't matter)
So, I don't really understand where you got the almost 5 USD from. Yes, you have fees obviously, but TransferWise rather shows you the real exchange rate and fees, instead of using some bad exchange rate and hiding the fees in the rate. That's transparency.