Once a month, I host a LAN where we play various titles, but our 2 hour "warmup" with snacks and social interaction is spent on a desktop playing >= 8 player games. I've had great luck with Regular Human Basketball and Splody, and then also countless 4 player games. I own two Microsoft Xbox Wireless Adapter for Windows 10 (new version supporting 8), and was hoping to have both hooked up for 16 controllers. However, only one works at a time. Even with 1, many of these games that have "8 player local multiplayer shared screen" don't register past 4 controllers.
I've been trying to read on DirectInput vs XInput, so I guess I'm looking to confirm that XInput has a cap of 8, DirectInput is (sort of) unlimited, but if the game developer doesn't implement DirectInput, then you're out of luck? Is there anything I, as the user, can do to ensure I have all the controllers properly synced whether it's wired via USB, wireless via dongle, wireless via Bluetooth, etc.?