You can probably get away with it at night, well after dark. But take everything including her nesting material, as she will be more likely to accept the move this way. I would not do this unless you have a good way to confine her, such as a broody pen or large dog crate, as she will most likely to try to move back.
Or -- you can leave her alone. It's not really such a bad spot, since it's in the coop. Many a chick has hatched in an old fashioned hay loft. They ordinarily survive the jump/fly/fall from the height just fine. Once they're down, mama will follow and make a nest in a different spot. The only trouble will be if one leaves the nest before mama and the others are ready. Ordinarily, the new chicks will stay under mama for a day or so, til she leaves the nest to teach them to eat and drink.
Good luck!