code.py

# Запрос:
company_subquery = (
    Order.objects_clear.annotate(
        company_pk=F("client__company_id"),
        company=Coalesce(
            F("client__company__alias"), F("client__company__name")
        ),
    )
)
company_name_subquery = company_subquery.values("company")[:1]
company_pk_subquery = company_subquery.values("company_pk")[:1]
received_companies = (
    Invoice.objects
    .annotate(
        received_company_pk=Subquery(
            company_pk_subquery, output_field=IntegerField()
        ),
        received_company=Subquery(
            company_name_subquery, output_field=CharField()
        )
    )
    # .order_by("id", "received_company_pk")
    # .distinct("received_company_pk")
    .values_list("received_company_pk", "received_company")
)

# Результат:
# <QuerySet [(4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), (4, 'MDK'), '...(remaining elements truncated)...']>

# Если раскомментировать `.distinct("received_company_pk")`, то получаю
NotImplementedError: annotate() + distinct(fields) is not implemented.