Yes it is possible. I got it working with the free ‘Side Chain Compressor’ from Slim Slow Slider:
http://www.ismusic.ne.jp/slim_slow_slider/vst/#sidech
When you import the stereo version of this plugin, Podium will create two input mappings and one output mapping. The first input mapping is the regular input and the second mapping the side chain input. The plugin thus is configured as a global plugin and not an insert plugin, since it needs to be assigned to several tracks. Because the plugin is configured with separate input and output mappings, it is in itself set up as a bus, so on the tracks you assign the input mappings you use the send dial to control the input.
There is a mono version of the SideChainCompressor plugin, which will be imported as a single stereo in/out insert mapping. That’s because Podium cannot determine that it is actually two mono inputs. You need to split the stereo input mapping yourself after import.
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