The attributes of a JSON object value should undergo expansion.

[jason-fox]

Create an Entity with a Property whose value is a JSON Object.

curl -iX POST \
  http://localhost:1026/ngsi-ld/v1/entities \
  -H 'Content-Type: application/ld+json' \
  -d '{
    "id": "urn:ngsi-ld:Building:store001",
    "type": "Building",
    "address": {
        "type": "Property",
        "value": {
            "streetAddress": "Bornholmer Straße 65",
            "addressRegion": "Berlin",
            "addressLocality": "Prenzlauer Berg",
            "postalCode": "10439"
        }
    },
    "@context": "https://raw.githubusercontent.com/FIWARE/tutorials.Relationships-Linked-Data/master/data-models/user-context.jsonld"
}

The supplied User @context includes subattribute term mappings as shown:

{
   "@context" : {
        "address": "schema:address",
        "addressCountry": "schema:addressCountry",
        "addressLocality": "schema:addressLocality",
        "addressRegion": "schema:addressRegion"
     }
}

Then receive the entities by type as shown without supplying a User @context:

curl -G -X GET \  
  'http://localhost:1026/ngsi-ld/v1/entities' \
  -H 'Accept: application/ld+json' \
  -d 'type=https%3A%2F%2Furi.fiware.org%2Fns%2Fdata-models%23Building' \
  -d 'options=keyValues'

Orion returns:

[ {
  "id" : "urn:ngsi-ld:Building:store001",
  "https://schema.org/address" : {
    "addressLocality" : "Prenzlauer Berg",
    "addressRegion" : "Berlin",
    "postalCode" : "10439",
    "streetAddress" : "Bornholmer Straße 65"
  },
  "@context" : [ "https://uri.etsi.org/ngsi-ld/v1/ngsi-ld-core-context-v1.6.jsonld" ]
} ]

Since address.value is just a JSON-LD @value, the attributes of the object should undergo expansion. The expected response is:

[ {
  "id" : "urn:ngsi-ld:Building:store001",
  "https://schema.org/address" : {
    "https://schema.org/addressLocality" : "Prenzlauer Berg",
    "https://schema.org/addressRegion" : "Berlin",
    "https://schema.org/postalCode" : "10439",
    "https://schema.org/streetAddress" : "Bornholmer Straße 65"
  },
  "@context" : [ "https://uri.etsi.org/ngsi-ld/v1/ngsi-ld-core-context-v1.6.jsonld" ]
} ]

[kzangeli]

Yeah, well aware.
Misunderstanding back in 2018.
For Orion-LD, we need to work out an approach on how to fix this.

IMO, the value of "value" belongs to the user and thus is sacred and should never ever be modified in any way.
However, unfortunately, the API spec of NGSI-LD states otherwise and yes, this is an important bug (undetected by external users since ... always - note that Jason is a colleague of mine in the FIWARE Foundation :() and we need to find a good way of expanding those attribute values, via a DB adaption script, or something similar.