All json files are cleared in the case that may be an issue. This was reproduced in single player as well to ensure no other mods conflict.
When attempting to use /pokeedit ign slot ev(Stat): , it appears that the stat page does not reflect those effort values. It simply remains the same or negates stats, even when using dominant natures or neutral ones. Attached is a video as well displaying the issue at hand, and how my Azumarill did not change stats.
If a video of negating stats is needed, that can be provided as well.
Video:
https://www.youtube.com/watch?v=cpVIkrpgmdI