Most money transfer providers make money two ways: a stated transfer fee, and a markup on the exchange rate compared to the real mid-market rate.
A '$0 fee' transfer can still cost you more overall if the exchange rate is marked up 2-4% below the mid-market rate — money you'll never see reflected as a line-item fee.
The only way to know the true cost is to compare the total amount your recipient will receive, in their local currency, across providers for the same send amount.
Dicha shows the total your recipient receives before you confirm every transfer, so there's nothing to reverse-engineer.