Karabiner is a powerful and flexible keyboard customization tool for macOS. It provides extensive control over keyboard input and allows users to remap keys, create complex keybindings, and customize keyboard behavior. Karabiner is not a window manager: it has no built-in commands to move, resize or switch windows.
Some users still make Karabiner part of a keyboard-driven window workflow by binding keys to actions handled by other tools. Its features that are relevant here include:
SMBAct offers a range of features that make it a compelling alternative to Karabiner for window management. SMBAct allows users to control and manage windows using customizable keyboard shortcuts, including the ability to move, resize, minimize, close, and fullscreen windows. It supports multiple displays, offers extensive customization options for window size and position, and includes features like fuzzy search and window blacklisting. Additionally, SMBAct is a cross-platform application built for Windows, macOS, and Linux (macOS available now, Windows and Linux coming soon), making it a versatile choice for users across different operating systems.
Here you can find detailed information about SMBAct

