Theatrhythm Final Bar Line does not seem to be reading the controller for player 2.
Yuzu the emulator itself will detect that there is a second controller just fine, and the controller is enabled properly (light is green in the configuration for both player 1 and player 2), and the controller responds when buttons are pressed.
However, once the game is entered, the controller is not read at all. This issue happens on both Yuzu & Ryujinx with this game. I have tried using the controller for player 2 as player 1 and the controller is read properly. I have tried using the original controller for player 1 (that worked) for player 2 and the game does not read it.
Here is a pastebin link to the logfile: [ 0.096729] Input <Info> input_common\drivers\udp_client.cpp:UDPClient:139: Ud - Pastebin.com
(Small side note: sometimes this game gets stuck on the initial loading screen indefinitely, but it seems to happen at random. Closing/reopening will eventually fix it)
I did notice through searching that another user reported having a similar issue, but they said it resolved itself - I have not experienced that resolution: Theatrhythm Final Bar Line - duo - player 2 issue