We are working on a dataset control and came across a situation where we wanted to get additional entity fields data apart from which we are getting from Views, so we used property-set but as of now property-set doesn’t support Lookup, Multiset Option set, and few other types fields.
In order to handle this, we can use the addColumn method in the code and get the values for it.
However, our issues are that the property-set (usage=input) now only allows us to type the field value, the dropdown is greyed out. But, I remember this being not the case initially and surprisingly it works for field control and we can either enter a hardcoded value or select field we wanted the same thing to work on dataset control.
We also tried using the property tag, but, the output is the same.
You can find attached the controlmanifest.xml for our control.