This is about running 8BitDo's Firmware Update tool for Windows in Wine. It can be used for updating newer 8BitDo devices that may not be supported by fwupd on Linux.
This tool needs Segoe UI Symbol font, on Arch this font is provided by ttf-ms-win10-auto package. For other distributions there is install script.
You will have to let Wine access device's HID interface for updating firmware, something like this should work for 8BitDo Ultimate Bluetooth Controller
sudo nano /etc/udev/rules.d/71-8bitdo-boot.rules
# 8BitDo Ultimate Bluetooth Controller's boot HID interface