Hi!
For me and most of Linux user (or users that don't have Photoshop license) I think very painfully to use Gimp plugin for export from PSD files, because sometimes it crashes on Photoshop groups and you need to ungroup all layers, you need to don't forgot revers them cause it exports draw order reversal (very annoying when you forgot that and need export it again or change draw order manually) :S.
Gimp have weaker support for PSD than Krita, and when you create all art in Krita or some artist send you PSD for animation you need to use Gimp for export it.
When Krita 4 release, it have feature for create python plugins https://docs.krita.org/en/user_manual/python_scripting/introduction_to_python_scripting.html.
There are is unofficial plugin https://github.com/chartinger/krita-unofficial-spine-export, but it will be grate to create official plugin, to avoid Gimp in work.

Hi. Yes it works good, but have one problem. Krita support multiply layers with same name, and if you have they exported json is crashing on import (small bug, need to add suffix when export if layer duplicate name), in other cases It works well (More faster then Gimp). About license author of script use MIT license, and will not deny if you use it.