This report categorizes these projects into three distinct types: (virtualizing one keyboard as two), Hardware Replacements (physically splitting standard keyboards), and Firmware Tools (for custom split mechanical keyboards). The most prominent software tool in this category is Toshiya Kondo’s "Keyboard Splitter," which addresses the specific gaming niche of "multiboxing."
If both players are controlling the same character, make sure "Block Original Input" is checked in the settings. github keyboard splitter