The Lightning Network Now Supports Transactions Across Blockchains

Previous atomic swaps that I have done were on-chain, and had the on-chain limitations of slow [transactions] and high transaction fees,” Litecoin creator Charlie Lee told Bitcoin Magazine, referring to an older trick to exchange different types of coins trustlessly. “Off-chain atomic swaps are significantly better. They are instant, [have] low fees, and better protect one’s privacy.
— Charlie Lee