Can I customize the shifter paddle or blip operation on 11-speed Red eTap? E.g. have the left paddle shift up, or connect two wired eTap Blips to one shifter and have each Blip shift in a different direction?

No, RED eTap 11-speed is a closed system and is not programmable. Only the functions of our 12-speed AXS shifters can be customized, via the AXS app.

Note: 12-speed SRAM AXS controllers that are paired to 11-speed SRAM Red eTap derailleurs will not be configurable in the AXS app.