MLPFictions is the French equivalent of FIMFiction, you can find various translations and lots of original works there! (Alternatively, we have a FIMFiction group here.)
As for me, I have been translating things for a few years already. (I study English and pretty much everything I do involves English one way or another.) I do not take on requests, but I will make sure to let you know if your work caught my interest.
Feel free to ask anything. :)