For VST plug-ins, yes - unfortunately this is not possible for Audio Unit plug-ins. For VST plug-ins, do the following;
1. Create a folder for your non-automap VST plug-ins wherever you like (as long as it is outside your host application's VST search path).
2. Then, in the Plug-in Manager, add that path to the VST search paths in the box at the bottom.
3. Automap-enable the plug-ins in the usual way.
4. Finally, move the "pluginname (Automap)" files out of the folder you created and back into your host's VST search path.
Now, only the Automap plug-ins will appear in the host.