A short report on Bilibili by the Navy observe channel "Phantom Longbow" suggests that, based on their observations, the second batch of four Type 054B shows no visible improvements over the first batch; at least the propulsion system and VLS are completely identical. The only uncertainty is whether the YJ-83 will be replaced with the YJ-12.
Replacing diesel engines with gas turbines or upgrading H/AJK-16 to HT-1 VLS require major modifications to the hull design and center of gravity. If this wasn't implemented in the first batch, it means it won't be implemented in the second batch either, as it's not cost-effective.
These drastic changes are most likely to occur in the next-generation FFG, which may still have two ships in the first batch.