Big-B Okay, I figured it out. When you added your bunq account you selected USD as the currency of your bunq account, but this was wrong, as this only works with SWIFT and is much more expensive as you could see.
When you add a new recipient (or own bank accounts) you should select the currency of the recipient/bank account, not the currency you want to send money from. Your bunq account is in EUR, so you should select EUR obviously.
TransferWise doesn't only offer you USD, as you might could see - there are a lot of currencies available, it doesn't really make sense to add your account 200 times for each currency.
When you start a transfer you then select the currency you want to send money from, and then the currency you want to send money to.
Solution: Remove your bunq account from transferwise.com and add it again, with EUR as you want to receive EUR on your bunq account.