@thewardrums to route separate channels in the DAW through your plugin you need to modify the HISE source code a little bit. It’s not a feature that is natively supported in HISE. It requires a bit of knowledge about JUCE and C++. Note that different SDKs (AU, VST3, AAX) have unique ways of handling channel counts and routing, as do different DAWS (ProTools and Logic support mono channels for example, whereas Ableton doesn’t).

It's not a beginner friendly task but you want to look into HISE's buses support and properties:

If you want to setup sidechain within the plugin however that can be accomplished in Scriptnode. There are a couple of examples in the snippet browser that show you how to set this up.