Benefits as an Elite Plus
As well known, CZ is not keen on providing more services to Elites than normal passengers. They don't even care about their own Elites (Silver/Gold members of the Pearl Club). Also, CZ is not the one having an intimate relationship with DL. Therefore, I'd say you should expect all, but also only, benefits for ST EP. But if you request additional benefits, for example, seats with more legroom, I don't think they will mind offering them to you.