"through exchanges" is correct and can be used in written English.
For example, you could use it in the sentence "Families stay connected through exchanges of letters and emails."
Humans interact with urban microclimates through exchanges of energy.
UPSH plants will interact with the surrounding porous medium through exchanges of groundwater.
The government will offer subsidies to help low-income people buy insurance through exchanges.
Unfortunately Obamacare stipulated that subsidies would be available only through exchanges "established by the State".
Americans are supposed to be able to start shopping for insurance through exchanges in October 2013.
This could make broadband available through exchanges serving 99.1% of the UK population.
As more ads are bought and sold through exchanges, it could transform the ad marketplace.
The King challengers say the law only authorizes subsidies through exchanges established by the state.
There is no limit to how many times an investor can delay paying taxes through exchanges.
Obamacare provides subsidies to the cash-strapped when they buy health insurance through "exchanges established by the state".
Around 90% of bets placed through exchanges and more than half of bets made online in Britain are through Betfair.
