db={"orders":[{"_id":1,"userId":2},{"_id":2,"userId":1},{"_id":3}],"profiles":[{"_id":1,"uniqueId":1,birthDate:"03-05"},]}

db.orders.aggregate([{"$lookup":{"from":"profiles","let":{"userId":"$userId",},"pipeline":[{"$match":{$and:[{$expr:{"$eq":["$uniqueId","$$userId"]},},{$or:[{"birthDate":{"$regex":"03-05"}}]}]},},{"$project":{"userId":1,"uniqueId":1,"mobileNumber":1,"whatsApp":1,"emailId":1,"lastName":1,"firstName":1,"address":1,"signature":1,},},],"as":"profile",},},])