Yes, 3Pool will be able to mint crvUSD if there is a crvUSD +3crv pool available. This is because 3Pool is a decentralized liquidity mining platform that allows users to mint rewards by providing liquidity to a pool. If a crvUSD +3crv pool is available, users will be able to deposit crvUSD and 3crv into the pool and receive rewards in return. The rewards will be generated from the fees collected from trading activities in the pool. This is a great way to earn rewards while providing liquidity to the crvUSD +3crv pool.