20% in Euro of Crypto value.
This is not clear at all.
Math tells that this 20% is not the interest.
Then what's that? 20k EUR is 20% of your crypto holdings worth, meaning that you plan to put on escrow crypto that today worth ~100k EUR?
Also the way the fiat is transferred needs to be also cleared up, but that would be the second point. First you have to prove you have plenty of collateral.
That's exactly what I mean. I put about 100k€ of crypto as collateral. Transfer as normal SEPA transfer. 100k in crypto just in case crypto price goes down.