[Inderjit Sanghera]

Legolas Greenleaf of Gondolin and Legolas of the Nine Walkers aren't the same person. legolas of Gondolin, was a Gnome, and I belive that the time in which the fall of Gondolin written, only Noldor resided in Gondolin, whereas later on, it was a mixture of Noldor and Sindar. But if the two Legolas's were the same, then surely Tolkien would've mentioned it, like he did with Glorfindel. I think it is either him re-using a character (There was also a blind Elf called Gimli, in that book) or it is simply a re-used name. For example, there is a Galdor in LoTR and one in FoG. I think that no Elf share the same name thing may have been discarded.