We have been seeing a lot of characters who look similar to characters from The Wind Waker/Phantom Hourglass, presumably because they are descendants, but now art has surfaced of what appears to be an old face from Wind Waker, though a much older face than before thanks to the time gap.

Whether this is really Niko is not yet known until someone translates, though the portrait of Niko as a young man at sea seems to suggest it.

You can see more scans here.