There are 2 repositories under keyboard-mapping topic.
SharpKeys is a utility that manages a Registry key that allows Windows to remap one key to any other key.
A tiny sandboxed Dyon scripting environment for evdev input devices that lets you do e.g. xcape in Wayland | now on https://codeberg.org/valpackett/evscript
QuickCut is a cross-platform keyboard manager that both facilitates key mapping and allows the configuration of global hotkeys triggering user defined actions.
Key mapper for 8BitDo's Retro Mechanical Keyboard
Linux keyboard mapping utility
Arduino PS2 keyboard International Keyboard mapping from PS2KeyAdvanced and return as UTF-8
Joystick to keyboard mapping windows desktop app
Keyboard Key Remapper on Windows with dual-role keys, layers, mouse emulation and more.
Swap brackets and parentheses for Common Lispers on Windows
Dual function keys for home row; with support for fast (touch) typing.