you will need to map buttons to keyboard keys using a 3rd party remapping program like AntiMicro.
you can do this with a steam controller (or ps4, xbox, switch) through steam, but i need to know more to tell you how to set it up (not familiar with 7thheaven and what it does to possibly bypass steam)
this question is for anyone that knows, if you are logged onto steam, and run 7thheaven and then launch ff7, does steam say you are playing final fantasy 7, 7th heaven, or does it not even see you are playing a game and your username remains blue? (turns green when you launch a game through it, and says the game)
also do you do the button remapping in 7thheaven program or inside the game's config? in 7th heaven right?
steam's button mapping is quite extensive, you can make a config with it with not only games but pretty much any program by using steam to launch said program
i use steam to launch my browser when i'm using my tv as the display and am trying to watch videos, and have a special config just for it to pause/play/back/forward/etc ( works with steam link too

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