GP2040-CE VS DaemonBite-Arcade-Encoder

If you're making a home made arcade stick, check out the GP2040-CE project - https://github.com/OpenStickCommunity/GP2040-CE

It's got low latency and good compatibility for a bunch of platforms. Even some compatibility for PS4.

My advice is to rework your mixbox, as it is pretty much the only long-term solution. Personally, I would swap out the keyboard microcontroller and instead wire your keyswitches to a PiPico running the GP2040-CE firmware. That way you can easily remap the keys, as well as select between your controller acting one of these:

Talking about RP2040 powered controller firmware. GP2040 is an amazing project, which is used a lot in the Fighting Game Community where custom controllers are common. https://github.com/OpenStickCommunity/GP2040-CE

you can connect to it the same way as a brook pcb (without soldering), and its firmware is far more customizable with great input latency test results. you can read about the firmware here: https://github.com/OpenStickCommunity/GP2040-CE

congrats on the build & thank you for sharing your experience! if I may suggest you to take a look at the open source project using the Raspberry Pi Pico and other boards based on the RP2040 microcontrollers. https://github.com/OpenStickCommunity/GP2040-CE

In theory, one would only need to use the Pi Pico (Using the CP2040-CE Firmware), since many play fighting games on PC; At least, that I am aware of. This, along with a few other things, would make it an "okay" controller at best, IMO.

I suspect GP2040-CE will pretty soon have some capability to switch between profiles on the fly, though of course you can never predict these things with volunteer open source development. In any case, I'd recommend GP2040-CE as an option over the Brook. You can buy a Pico breakout such as this one for cheaper than the Brook & have access to all sorts of cool features now and in the future.

This

Microcontroller: Arduino pro micro clone. Sells for peanuts on Ali Express. I have no coding experiennowledge. I tried to use this guide, but it only made the controller show up as a generic controller on windows/Linux. SF6 Didn't recognise the controller. So I programmed the Arduino as a keyboard and now it works fine on PC and Steam Deck.

I've had a great experience with Arduino Pro Micro's running the DaemonBite firmware, and the RPi Pico GP2040 firmware should be similarly great. Both have extremely low latency. The Brook Universal board is another good one. Other than that, I usually just use either a DualShock 3 pad over USB or a wired 360 pad. I also like the iBuffalo SNES pad and Logitech Precision pads.

The NEO2USB is just an Arduino running the DaemonBite firmware. If you (or someone you know) can do basic soldering and can follow a tutorial for loading code onto an Arduino you can DIY an identical adaptor for about a third of the price of the Neo2SD. If you can get access to a 3D printer there are also case designs available for free.

If you can solder (or know someone who can), you could swap out the usb encoder for a Daemonbite and that would give you less than 1ms of input latency.

I'm not sure, I only use it for console controllers, but I would assume so. This GitHub repo has the pinout for arcade sticks: https://github.com/MickGyver/DaemonBite-Arcade-Encoder

I had one of those pcbs, the input lag is bad and inconsistent, the build quality it's very cheap, and has no xinput support... Nowadays are better alternatives like Brook Zero-Pi, Tachyon PCB, or DIY stuff like GP2040-CE ( https://github.com/OpenStickFoundation/GP2040-CE ) or DaemonBite ( https://github.com/MickGyver/DaemonBite-Arcade-Encoder )