Could someone please tell me why there is a Mono version of plugins.
What practical advantages and application would a mono version have?
Mono channels are still being used a lot, for example in recording and analog mixing.
Imagine using a analogue console for your mixes. If a DAW only had stereo channels, an instrument would always need 2 outputs of your converter and use 2 inputs of your desk. This is quite inconvenient if you want to spread out your drum tracks on the console, as it would require a lot of channels on your board. That's why a lot of people still use mono channels. And thus we provide mono plug-ins for them ;-)
Hope this answers your question.