db={"totalpoints":[{"_id":{"playerId":"2331078","tournamentId":"197831"},"playerName":"xyz","pointsTotal":0,"__v":0}],"team":[{"_id":{"teamName":"BILALATI6449","tournamentId":"197831"},"tournamentName":"Amanora Cricket Championship 2021","player1":{"playerId":"2331078","tournamentId":"197831"},"player2":{"playerId":"196713","tournamentId":"197831"},"player3":{"playerId":"113069","tournamentId":"197831"},"player4":{"playerId":"249044","tournamentId":"197831"},"player5":{"playerId":"113129","tournamentId":"197831"},"player6":{"playerId":"181056","tournamentId":"197831"},"player7":{"playerId":"658022","tournamentId":"197831"},"player8":{"playerId":"182623","tournamentId":"197831"},"player9":{"playerId":"249047","tournamentId":"197831"},"player10":{"playerId":"658053","tournamentId":"197831"},"player11":{"playerId":"658057","tournamentId":"197831"},"__v":0}]}

db.team.aggregate([{"$match":{"_id.teamName":"BILALATI6449","_id.tournamentId":"197831"}},{"$addFields":{"newField":{"$filter":{"input":{"$objectToArray":"$$ROOT"},"as":"p","cond":{"$regexMatch":{"input":"$$p.k","regex":".*player*."}}}}}},{"$lookup":{"from":"totalpoints","localField":"newField.v.playerId","foreignField":"_id.playerId","as":"players"}},{"$project":{_id:1,tournamentName:1,players:1}}])