Inserts and bus inputs and outputs in Qtractor are intended to communicate with external applications.
So yes, you will always need an external application.
They are not suitable for what you intend to do.
For internal signal sends use AuxSends.
Right click on the plugin box: Inserts/Audio/Add Aux Send
They are much easier to handle.
The latest version of Qtractor 1.3 makes them much more flexible.
In fact any tutorial you find about sends will confuse you, because it will refer to old limitations that no longer exist and propose inadequate workarounds.
Inserts and bus inputs and outputs in Qtractor are intended to communicate with external applications.
So yes, you will always need an external application.
They are not suitable for what you intend to do.
For internal signal sends use AuxSends.
Right click on the plugin box: Inserts/Audio/Add Aux Send
They are much easier to handle.
The latest version of Qtractor 1.3 makes them much more flexible.
In fact any tutorial you find about sends will confuse you, because it will refer to old limitations that no longer exist and propose inadequate workarounds.