query: SELECT ?item WHERE {
    SERVICE wikibase:mwapi {
          bd:serviceParam wikibase:endpoint "ja.wikipedia.org";
                          wikibase:api "Generator";
                          mwapi:generator "transcludedin";
                          mwapi:gtilimit "max";
                          mwapi:titles "Template:コンピュータゲーム";.
          ?item wikibase:apiOutputItem mwapi:item.
    }
    FILTER BOUND (?item)
    FILTER NOT EXISTS { ?item wdt:P31 [] }
  }