It doesn’t do anything afaik. The box has only one scart assuming you mean a HDR1000S and it’s an output.
There is no way to chain analogue inputs (there aren’t any) via the box to the analogue outputs.
Perhaps the box originally was expected to have a second scart and the remote was designed with this in mind. The Foxsat-HDR was the last satellite Humax pvr to offer scart input and output sockets.
In any case to use this capability you would need to connect to a TV via scart and HDMI. No PVR afaik has the capability to digitise a analogue input and output digitally over hdmi. A higher end AV receiver would be needed to manage this.