China’s cocktail of pro-electric policies is a challenge for global automakers, as foreign manufacturers can access subsidies only via joint ventures with local partners, producing cars under new made-for-China brand names such as Denza. But those brands lack the cachet of established foreign marques, and cost more than most local brands even after subsidies. That’s in part because Chinese automakers are more aggressive in lowering their costs regardless of quality, said an executive at a multinational auto parts firm.