joystick_port_1

The option documentation is properly formatted yet

Example: SPEED-LINK COMPETITION PRO #2

The device connected to port 1. If not specified, a the first joystick/gamepad connected to the computer will be used, if the joystick/gamepad is supported. Otherwise it defaults to keyboard emulation (cursor keys + right CTRL). To force keyboard emulation, specify "keyboard".

You can also choose to use specific gamepads/joysticks in the ports. In this case, you specify the device names. If you have more than one device of the same model, the second is referred to by appending a space and #2 (and so on). The device names are case insensitive.

To force specific joystick devices in both joystick ports, you configure something like this:

joystick_port_0 = SPEED-LINK COMPETITION PRO #2 joystick_port_1 = LOGITECH CORDLESS RUMBLEPAD 2 USB

Source: https://github.com/FrodeSolheim/fs-uae/blob/master/docs/options/joystick_port_1