That is only true for managers on different hosts. Communication between managers on the same host does not go through the proxy.
For redu switches it probably does not make much sense to define an error weight to the proxy (might it switch faster?) but the feature allows more, for example to configure an alert on the manager going down. This is currently not possible.
You cannot configure an error weighting for the MxProxy as it is not connected to the Data- or Event-Manager as other managers in WinCC OA.
Therefore, in WinCC OA there is no connection information available and this is the cause why it cannot be configured.
Best Regards
Leopold Knipp
Senior Support Specialist