Yes. it is p2p exchange between SBD and KRWP token (one of steem engine token. it aims KRW pegging).
I found those about escrow.
https://steemit.com/sip/@dan/escrow-sip-steem-improvement-proposal
https://steemit.com/escrow/@xtar/open-source-standalone-gui-for-steem-escrow-transactions.
If I will use this function or make a system with escrow api, risk of exchange should be lower..
Thank you!