Blynk.syncAll was disabled when Blynk 2.0 was initially released.
It will now work with virtual pins (there is currently no support for digital pins in Blynk 2.0), but only if the datastream has this advanced setting enabled…
More info here…
In this issue I asked the question…
BLYNK_WRITE_DEFAULTto trigger for any datastream that has this option turned on and doesn’t have an explicit
I didn’t receive an answer, but my testing has shown that yes, this does work as expected with BLYNK_WRITE_DEFAULT.