[{team_a:{team_score:94,team_name:"team_1",players:[{id:"604f00d43776e45a448628f9",username:"test_1",score:"33",rank:"1",prize:15.4,},{id:"60058dd9b88cc1a1e40f2f54",username:"test_2",score:"31",rank:"2",prize:15.4,},{id:"60058dd9b88cc1a1e40f2f55",username:"test_3",score:"30",rank:"3",prize:15.4,}],},team_b:{team_score:62,team_name:"team_2",players:[{id:"602ce34a39c7496600940774",username:"test_4",score:"32",rank:"1",},{id:"60058db6b88cc1a1e40f2f4f",username:"test_5",score:"30",rank:"2",},],},}]

db.collection.aggregate([{$unset:["team_a.players.id","team_b.players.id"]},{$project:{"team_a":"$team_a.players","team_b":"$team_b.players","all_winners":{"$concatArrays":["$team_a.players","$team_b.players"]}}}])