When sending an asset to another address standard network (miner) fees apply. Miner fees are displayed before you broadcast your transaction. ShapeShift does not charge any additional fees on top of the network fee when sending a transaction. While these fees are dynamic, they are preset and there is no way to set customized miner fees at this time.
It is important to note that anytime you are sending ETH or an ERC20 token, there must be a sufficient balance of Ethereum (ETH) in your wallet to cover the cost of gas (another name for transaction fees). If you do not have enough ETH to cover this cost, you will not be able to send the asset.
If you need to purchase some ETH, you can do so directly in our app via Banxa. Instructions on how to do so can be found here.