I would use 'AntiMicro' instead of Joy2Key as AntiMicro is open-sourced and more secure. You know exactly how it works and that it isn't doing anything shady in the background. Also has Linux support!
https://github.com/AntiMicro/antimicro
There are also a few presets, including one that I contributed for Guild Wars 2 :)
Check out the presets and then adjust for your needs. If you still need further assistance, I can help you out live via Discord. I've got a link in my itch profile.