There's a bit more to it than that but not much. It just takes L and R inputs and a control parameter then performs a function on each input and sends them to the outputs.
If you're using a stateless function with a single parameter, you are exactly within the bounds of the math.expr node which does exactly this (not more and not less).
Link Preview Image HISE | ScriptNode | exprA dynamic expression node that uses a SNEX math formula for processing the signal.
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