Coinbase released BSV users got from the BCH fork. Anyone who wants to sell it or buy more should use another exchange like Bittrex or Binance.
To move your BSV to these exchanges, withdraw your BSV from Coinbase to a Bittrex or Binance BSV wallet (carefully following the steps listed by those wallets).
Coinbase has no plans to allow BSV trading.
"Coinbase Release User’s BSV; Users can Trade it on Bittrex or Binance" contains information about the following Cryptocurrencies:
Bitcoin Cash (BCH) + Bitcoin SV (BSV)