Synchronized Wagon Filters
A Factorio mod to synchronize wagon filters.
Usage
Press Shift+E (configurable) when hovering a cargo wagon to show the GUI. Each cargo wagon can be assigned to a group. All cargo wagons belonging to a group can be updated at once.
As for now, I couldn't find an efficient way to synchronize wagons automatically when the player configures a filter. The synchronization must be manually triggered by pressing the 'Broadcast' button in the GUI.
Compatibility
Should work with modded cargo wagon as long as they use the 'cargo-wagon' entity type.