Database
[{"name":"C","dateTime":"Oct 19 14:52"},{"name":"B","dateTime":"Oct 19 14:52"},{"name":"A","dateTime":"Oct 19 16:52"},{"name":"C","dateTime":"Oct 19 15:52"},{"name":"B","dateTime":"Oct 19 16:52"}]
Query
db.collection.aggregate([{$group:{_id:"$name",docs:{$push:"$$ROOT"}}},{$sort:{"docs.dateTime":1,"docs.name":1}},{"$unwind":"$docs"},{"$replaceRoot":{"newRoot":"$docs"}}])