Database

[{"_id":ObjectId("5f2e8e0d4976ed2c04fc2e90"),"reference":"5f2e8e0d4976ed2c04fc2e8f","id":"5e87187f6e8c15766e6994f8","name":"no name","items":[{"_id":ObjectId("5f2e994336caf138c13560fc"),"requestedItems":"5e87187f6e8c15766e6994f8","name":"no name",},{"_id":ObjectId("5f2e994336caf138c135601c"),"requestedItems":"5e87187f6e8c15766e6994f8","name":"no name",},{"_id":ObjectId("5f2e994336caf138c135201c"),"requestedItems":"5e87187f6e8c15766e6994f8","name":"no name",},{"_id":ObjectId("5f2e994336caf138c139521c"),"requestedItems":"5e87187f6e8c15766e6994f8","name":"no name",},{"_id":ObjectId("5f2e994336caf138c139504f"),"requestedItems":"5e87187f6e8c15766e6994f8","name":"no name",},],"createdAt":ISODate("2020-08-08T11:35:41.675Z"),"updatedAt":ISODate("2020-08-18T13:34:43.077Z"),"date":"8-8-2020","__v":0}]

Query

db.collection.aggregate([{$match:{"id":"5e87187f6e8c15766e6994f8"}},{$addFields:{items:{$slice:["$items",-3]}}}])

Result