This is a toughie. Maybe a small room divider that could extend from the stone wall just enough to hide the sink but not obstruct traffic. An expensive option would be renovating to move the sing behind the wall and leave that as open counter/bar space out in the open.

I don't think it's noticeable at all given the size of your home. If it was a 1,200 sq ft house, it would be a different matter, but the sink is so far back from the front door, it really isn't that big of a problem. I honestly had to look closely at the first picture to even see it.

The sink would be visible eventually upon entering into the main living areas.