@Tempest7MR you should be able to utilize the new launcher for that… launching in pancake mode once* will write all the key and stick bindings.
*actually there are some weird bugs, fixed hopefully in U3, you might have to launch BMS this way 2 or 3 times to write all the necessary files. If you see “BMS-Auto.key” as the name of your key file, in game, then you’re good.