You cannot use your large amounts of cryptocurrency directly and receive a Golden Visa through it. Pursuant to the pertinent provisions of the Greek law, in order to be eligible for the Greek Golden Visa, the amount of the real estate purchase must be 250,000 euros at a minimum and must have been paid in full with a crossed bank check or bank transaction in the bank account of the recipient kept at a bank in Greece or a credit institution under the supervision of the Bank of Greece. Accordingly, provided that you can somehow convert your cryptocurrency into cash, then you could proceed to the real estate purchase with the aforementioned way and qualify for the Greek Golden Visa (provided, of course, that all the necessary requirements of the law are met).
Following a circular issued by the ministry of migration policy 23388/24/07/2018, it was clarified that in order to be entitled to the Golden Visa resident permit, the acceptable payment methods of the purchase price according to the Article 20 Law 4251/2014 are only two. The law 4587/2018 has also recently been voted that explicitly states that only the below mentioned two payment methods of a purchase price are accepted in the framework of the Golden Visa. The first option is the funds must enter through a bank transfer from your overseas bank account outside Greece either to your Greek bank account and follow by a bank transfer to the seller’s Greek bank account or directly to the seller’s Greek bank account. The second acceptable payment option is for the purchase price to be paid through the issue of crossed bank checks on the seller’s name by debiting your Greek bank account.