Hi, As always, ESRI what us to move to Pro but still not give basic functions available in arcmap for decade.
On of the main function, I use in arcmap, is replacing annotations by new one in my annotations after deleting the one needing replacement. So, when converting the labels to annotations, I use "Append" instead of creating a new database entry.
It does appear the ArcMap vs. ArcGIS Pro "convert labels to annotation" workflow is missing the Append parameter in the ArcGIS Pro side.
So my idea is simple, make APPEND available like always.