Along with three stablecoin pairs — BCH/USDT, BCH/USDK, and BCH/USDC — you can also buy BCH using the BCH/BTC trading pair. Currently, there is no BCH/ETH pair listed on OKEx. If you wish to buy BCH with ETH, you can deposit ETH to your OKEx wallet, trade it for USDT and then use that to purchase BCH.