[{"_id":"1","name":"name 1","created":"2020-07-21T08:11:18.414+00:00","tags":["red","green"]},{"_id":"2","name":"name 2","created":"2020-07-20T08:11:18.414+00:00","tags":["red","blue"]},{"_id":"3","name":"name 3","created":"2020-07-19T08:11:18.414+00:00","tags":["green","blue"]},{"_id":"4","name":"name 4","created":"2020-07-18T08:11:18.414+00:00","tags":["white","blue"]},{"_id":"5","name":"name 5","created":"2020-07-17T08:11:18.414+00:00","tags":["white","green"]}]

db.collection.aggregate([{$sort:{created:-1}},{$facet:{red:[{$match:{tags:"red"}}],green:[{$match:{tags:"green"}}],blue:[{$match:{tags:"blue"}}]}},{$project:{red:{$ifNull:[{"$arrayElemAt":["$red",0]},{}]},blue:{$ifNull:[{"$arrayElemAt":["$blue",0]},{}]},green:{$ifNull:[{"$arrayElemAt":["$green",0]},{}]}}}])