in order to exchange one cryptocurrency with another one you need to find someone else to do the exchange with.
- usually people use platforms such as exchanges to find that someone else to do the trade the easiest way.
- you can always find someone on other more peer to peer platforms like forums, other social media and do the trade but at a higher and different kind of risk. which is where escrows come in. you can also use multi signature features for this.
- and finally the newest and most awesome way is to use
Atomic Swap. it is a form of smart contract between two peers completely decentralized and without needing any kind of weird platform or anything like that. it is just a side channel. here is the concept:

both bitcoin and bitcoin cash are capable of doing this.
unfortunately i don't have more information that this to share but you can read more here:
https://news.bitcoin.com/this-developer-is-bringing-atomic-swaps-to-the-bitcoin-cash-network/https://github.com/decred/atomicswap/pull/37