General questions about converting fiats through crypto

So I have left the US for a studying abroad program and i am looking for the cheapest way to convert USD from my American bank to EUR in my Spanish bank. I have been thinking of buying a crypto with low fees (such as xrp) in dollars and turning around and selling it in euros right away through my kraken pro account and then withdrawing the euros to my Spanish bank account. Would this beat the high conversion rates and wire transfer fees provided by the Spanish bank and currency exchanges? I have already tried this in kraken pro with a small amount of USD (20 usd) but I’m running into issues with the withdrawal, my kraken pro account says after I sold my XRP for euros that I do not have any currencies to withdraw? Any help is appreciated thank you!!