The core is missing from the Android core downloader. It successfully builds from the build bot, but doesn’t work, and it can’t be uninstalled. It doesn’t load even removal options, and the phone isn’t rootable, which is required to access the /data directory.
In recent versions of RetroArch, you can go to settings > core > manage cores > swanstation > delete core. I’m not sure if it’s in the (now-old) version in the Play Store, but I would recommend sideloading the version from retroarch.com instead.
Side-loading the updated apk worked (for future reference: the x64 one, that is now named AArch64), but the core list was erased, and I don’t now if they were deleted or the old cores still linger.