db={Name:[{"First_Name":"Smith","Last_Name":"Smiths"}],Information:[{"Last_Name":"Smiths","Address":"Some street"}]}

db.Name.aggregate([{$lookup:{from:"Information",localField:"Last_Name",foreignField:"Last_Name",as:"Without_array"}},{$project:{First_Name:1,Last_Name:1,Address:{$first:"$Without_array.Address"}}}])