I’m really enjoying the classification grouping in the object viewer,
but don’t understand why is not possible to do a selection filter in the plugins like Advanced Reports or Object Filter,
is it possible to implement?
The classification option has been added only recently. In the newest version of Advanced Reports (which should come out this month, i.e. July 2019, after the new version of BIM Vision is released) the selection and filtering in classifications will already be available.