2-way redstone repeaters. Simply place 2 repeaters facing into each other. The plugin detects the changing state of the repeaters and will flip one the other direction to provide signal in either direction.

Note: there is a known glitch which can happen when both repeaters are powered at the same time, as can be seen in the video above.

Requires pxnCommonBukkit plugin: https://www.spigotmc.org/resources/pxncommonpluginmc.107049/

Discord: https://discord.gg/jHgP2a3kDx

Dev Builds: http://dl.poixson.com/mcplugins/Repeater2Way/