Hello,
If you have a fairly long time horizon to be in those funds and you are adding little by little, and when it is time to sell, do it little by little, I don't think that the currency risk won't be great.
As an example, 1 euro was $1.18 in the beginning. It isn't far from that now. Over the years, I think the movement has been between about $0.90 and $1.40 or so. But if you are adding slowly and then later subtracting slowly, it will work out.
The cost of a currency hedge might be more then you would benefit, assuming you are a long term investor.
Dave