I have my cheapo mini usb host shield (max3421e) connected up to a 3.3v 328p feather board. the arduino code translates the USB HID data to ps2 data for the fpga system - giving usb mouse and keyboard via a powered hub. I think I may have space for usb midi translation as well. I've been umming and aaahing about which MCU but the adafruit feather 328p seems best as it is 3.3v by default, supports all existing arduino libraries and has a lipo battery charger and pin which I can also use for battery backup to the sram controller (ds1314).

https://www.adafruit.com/product/3458

https://chome.nerpa.tech/arduino_usb_host_shield_projects/