I mean isn't it exactly the role of the 052D and its eventual successors? Its a small DDG that works together with big ones to provide overlapping cover, while also being able to lead small task forces.The primary threat to the PLAN is the USN submarine force and the next gen frigate would, before anything else, be designed as an anti-submarine frigate. However, the LRASM and F-35 are also a serious threat to PLAN's surface assets, as will the USMC be after reorganizing itself as a sea-denial force and introducing new missiles that can be deployed by small teams in the first and second island chains and all around the Pacific in very large numbers.
This means the PLAN requires not just an advanced ASW frigate, but also a ship similar to the Japanese Akizuki class frigates, which is optimized for defence against mass attacks by extremely stealthy, low flying cruise missiles at medium to close ranges. The 052D is not quite suited for such a role. They need a ship which is cheaper and can carry quad-packable missiles and has tall, mast-mounted fire-control radars.
It is possible for the 054A successor to fulfil both roles. It is also possible for the ship, using CEC, to act as the shooter of long range SAMs which are then guided by other assets like 055s, 052Ds, naval AEW planes and even carrier borne fighters. This requires it to have the same VLS as the 055 and the 052D.