Can I link the same Echoflex Wireless device to multiple inputs or outputs on an Echo Echoflex Interface (EEI)?
Technically you may be able to, but you should not.
When linked as inputs, wireless Echoflex control devices (switches/sensors) control Echo presets. The EEI lives in one Echo space and you can only have one preset active at a time in an Echo space. So if you link one Echoflex switch to two inputs, it will try to activate two Echo presets at the same time, which will not work.
When linked as outputs, wireless Echoflex output devices (controllers) act as Echo zones. Assigning the same device as multiple zones can cause issues when controlling zones or recalling presets on the Echo side. For example, if you link a controller to act as both Echo zone 1 and Echo zone 2, and those zones have different levels recorded into Echo presets, the controller will have trouble choosing which zone level to output.