Without other usb devices the keyboard works immediately. With them it takes 5 ish seconds for it to start responding. This is regardless of which device is discovered first (which I can manipulate), it seems to just wait for all of them. Is there a way to make it not do that?
I had an issue where one keyboard (worked with another one) worked in bootloader, but not when entering the encryption password after that. I believe I solved that by moving keyboard earlier in the module list in mkinitcpio.conf. Maybe something similar would solve your issue?
I did try messing with the hook order but it’s already as early as it can be.