What is the Wayland equivalent of xinput list?

On Debian the command is:

$ sudo libinput list-devices
# requires the libinput-tools package

On arch-linux:

# libinput list-devices

To list just the device names, no details, use grep:

$ sudo libinput list-devices | grep Device

You should be able to use sudo evemu-describe to list the input devices found in /dev/input/event*. It is interactive unless you give it a specific device from the list.

According to man 5 sway-input, you could use swaymsg -t get_inputs.