I had a idea

[HamBearGer]

Maybe we can try to code the script on the website,User updating them screemshot to the website,then maybe they move the bottoms and diy the keys Mapping,when they finish they design the website will output the json files.
However if most uesrs had their way to diy the keys mapping ,the will more easier to using this....
I know it might cost some if running on a server, hopefully this server can be deployed locally