Having the same issue here, Steam input doesn't work properly.
I have to do the following to get dinput controllers to work on NW.js (Webview 2 doesn't work at all).
- disable steam input while in-game
- press random buttons on the controller
- enable steam input in-game
xinput has the same issue with Steam Input on NW.js but you can just disable Steam input since native xinput works flawlessly