Technically speaking I think that is a greater warload than what the combined surface combatants of the Philippines, Malaysian and Vietnamese navies at this time can field, and is also greater than the firepower than can field even if we include submarines.
There is no doubt that those PLAN vessels have a far better Anti-air capability.
But those six vessels would carry, at the most, 72 ASMs amongst them. The 52Ds would probably carry no more than 16 ASMs each.
Just Vietnam and Malaysia alone can field, right now, the 22 vessels I detailed above to meet them and they would amass a total of 164 ASMs. And that does not include the six very modern SSK subs, which would pose a horrible threat to that PLAN force of six vessels.
My point was that the original comment about those six vessels being stronger and amassing more firepower than the combine navies of the three countries is not really correct.
Now, the scenario though of those six vessels attacking alone is simply not going to happen.
If the PLAN went into the SCS with the intent to clean it out, they would have probably 2-3 three task forces of 8-10 such ships, and that large effort would be supported by 10-12 subs and as much air power as the PLAN could muster down there...which with the three new airfields going in would be a lot..
Of course if that ever happened, it would not just be Vietnam and Malaysia they faced.
We'll leave that discussion completely alone because it is best not to go down that road here on SD, particularly since such war scenarios that they would engender are against the rules.