Pick & Update Families into Model tool in the Updaters drop-down helps pick and update multiple families into the current model if applicable.
After the button is clicked, it pops up a dialog for file picking.
After the OK button is clicked, an information box will appear to ask for confirmation.
If Yes is given, those family files will be updated into the current model one by one, in case it is already loaded. A progress bar will show how many files in total, which file is currently being processed, and what remaining time may be. An information box will finally show what have happened, good or bad.