When abroad you're able to use Gympass to access gyms that are available in your plan in two different ways:
1) If you go to a country that has the same currency as your own, there will be no adjustments in the amount of your unlimited plan prices and you can use gyms as normal
2) If you go to a country where the currency is different from your own, the price of your unlimited plan will decrease by 10% to factor in changes with the exchange rate. Rates are updated daily so you need to be aware of the value of your plan on a daily basis if you plan on using gyms in these countries
Note: in the advanced search options, there's an option called Gyms included in my plan: if you're searching gyms in another country with a different currency, this option will show you an estimate of what your plan is worth for that day in that currency.