You can turn this modular clamp-on controller into an N64 or GameCube gamepad

The X5 Alteron works with smartphones, tablets, and can replace faulty Joy-Cons on your Nintendo Switch.

GameSir And Hyperkin Reveal A Modular Pad With GameCube And N64 Layouts

Accessory manufacturers GameSir and Hyperkin have joined forces to produce a fully modular controller that's compatible with the Switch and Switch 2: the GameSir x Hyperkin X5 Alteron.
EDN

Developing a N64-Gamecube Controller to USB Adapter

A standard HID joystick is being implemented in this project by the microcontroller firmware since Nintendo 64 and Gamecube controllers are excellent controllers for several PC games. A standard HID ...