1) Do people’s positive, negative, healing energies mean anything in Islam? Or is this just a fad and baseless?
2) Do white or black feathers from birds found at home have any meaning in Islam? If yes, what do they signify?
People’s energies have a lot of meaning in Islam. The Prophet, upon him blessings and peace, said the friends of Allah are those who, when you see them, they remind you of Allah; he also said the evil eye is a reality. Our teacher Mawlana Shaykh Nazim often said that during the suhba a single person scratching their face brings down the spiritual level of the whole gathering. All goodness and harm without exception, however, can only exist by the permission of Allah and His will, contrary to non-Muslim beliefs.
As for deriving significance from bird feathers at home other than that the place needs dusting then no, and especially not bad omens, which is a pagan tradition.
Hajj Gibril Haddad