[{"Type":"A","Attributes":[{"Date":"2021-10-02","Value":5},{"Date":"2021-09-30","Value":1},{"Date":"2021-09-25","Value":13}]},{"Type":"B","Attributes":[{"Date":"2021-10-01","Value":36},{"Date":"2021-09-15","Value":14},{"Date":"2021-09-10","Value":18}]}]

db.collection.aggregate([{"$addFields":{"maxDate":{$max:"$Attributes.Date"}}},{"$addFields":{"Attributes":{"$filter":{"input":"$Attributes","as":"a","cond":{$eq:["$$a.Date","$maxDate"]}}}}},{$unwind:{path:"$Attributes",preserveNullAndEmptyArrays:true}},{$project:{Type:1,Date:"$Attributes.Date",Value:"$Attributes.Value"}}])