All sellers on dotCOM must sell in US dollars.
They (we) have no choice.
The tricky part will not be currency.
Your customer will see your asking price in his own currency in Search and in both his own and the seller's listing currency on the actual listing.
So if I search for sneakers on dotCOM, and find a Canadian seller who lists on dotCA, I will see his asking price in US dollars.
When I go to the listing I will see the price in US dollars AND in Canadian dollars.
The tricky part is shipping.
If your items cannot reasonable be sent Flat Rate, which is most items that are shipped Parcel (over 500 gr and 2 cm thick) you will have to do a LOT of massaging not to lose on shipping which varies not only by dimensions, weight and service, but also by Destination.
I can cost me $5 to ship a 3cm thick paperback to BC but $12 for the same parcel to go to Ontario for example.
