2 hours ago, Vitalik transferred 800 ETH to the 0xfEB...3B2 multi-signature wallet through the 0x1Db...EE6 (Vb 2) address, and then sold 190 of them.

The address where Vitalik transferred ETH is a 2/3 multi-signature wallet, and all three signature addresses belong to Vitalik:

0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 (vitalik.eth)

0x220866B1A2219f40e72f5c628B65D54268cA3A9D (Vb 3)

0xcC6DB3f018F861f54101531Ba293337d9978D2A2

In other words, the sale of ETH was done by Vitalik himself.

Multi-signature wallet: 0xfeb016d0d14ac0fa6d69199608b0776d007203b2