Hi! You can export a gedcom from wikitree containing your tree. You will have to import the gedcom in a piece of software abel to syncronize with FamilySearch (certified) https://familysearch.org/products. I've tried with Legacy and it works, compared to the possibilties in WikiTree, I do not find FamilySearch as an alternative at all, purely seen from a scientific point of wiev (no sources !!!).
There seems to be a lot of mythical genealogy on familysearch.org. I found "4th century Dagobert" there, for example. The current incarnation of the website also makes heavy use of Flash, so doesn't work with open source browsers.