CRYPTO20 (C20) is an “autonomous token-as-a-fund” and represents an Ethereum-based token. As of now, it is trading on a few exchanges with HitBTC being the most active exchange platform on its list. CRYPTO20 are so-called close-ended tokens. It means that no new tokens can be created. CRYPTO20 can only be purchased.
Decentraland (MANA) is currently based on cryptocurrency Ethereum protocol. You can trade this digital asset on the fair number of exchanges. For example, Binance features MANA/BTC currency pair.