Funny Possiblity, but no....these are just skin and eye charactistics.
Next your going to say that the post man has dark skin than others, so he must be related to the gerudo!
It just dosen't make sence, sorry for being the party pooper.
This is actually kind of....true. C'mon guys, I know there's not much to talk about in Zelda right now, but I literally facepalmed when I saw this thread today.
First, what relevance did the Sheikah have in MM at all? Closest thing we can get to is MAYBE they had something to do with the Lens of Truth being in the Goron Village, but really, where's the basis for that? Because I can't find any. Either that or somehow connect them to Ikana and the Stone Tower, but that's already taken up, what with the Ikana and Garo. No room for Sheikah there; you just can't make it work.
Now for Kafei himself, all that's there is a supposedly darker skin tone and red eyes. No in-game evidence based off of actions, or even in-game text that might even slightly lead one to consider that he's part of a race...... from another dimension. And even then, wouldn't his parents have to be Sheikah? His mother clearly isn't, and I don't see how you could spin that the Mayor somehow is.