Do you know yii2 module for money exchange, like https://exmo.com/exchange/?
Basic requirements:
-The currency exchange may have committed with and without registration.
-Currencies for an exchange:
bitcoin
litecoin
dollars
roubles
-Exchanges may be made in any direction.
-The module should not perform processing functions orders. It is only necessary to create order and output of a information.
I have the structure database MySQL.
Maybe somebody sells this extension?