IPSwitch is arguably the most famous . It uses a simple drag-and-drop interface. You drag a .pchtxt file (the patch) onto the executable, then select your ROM. The software validates the checksum to ensure the ROM is the correct version (e.g., Update 1.1.0). If it matches, the patching takes less than two seconds.
The Switch homebrew scene is shifting away from permanent ROM patching toward via LayeredFS. In Atmosphere CFW, you can place a .pchtxt file in /atmosphere/contents/[TitleID]/exefs_patches/ without ever modifying the original ROM. The patch is applied in RAM when the game boots. nintendo switch rom patcher