Blockstream to Launch First Sidechain for Bitcoin Exchanges

Could it be integrated easily with B&C Exchange, if needed?

The possibility of using B&C exchange to sychronize order books across exchanges is briefly described here

It implied that B&C is used to move funds between exchanges.

right. With lower fees, b&c is supposed to be able to offer a better price for any pair. Could b&c become the cheapest exchange out there? If yes, that is huge.