I have a player that was attempting to harvest an edelwood tree from forbidden arcanus in my pack The Cosmic Tree that crashed and is now unable to connect to my server.
They are getting this every time:

https://pastebin.com/1jyRFmXi

Minecraft 1.15.2
forge-31.2.45
WailaHarvestability-mc1.15.2-1.1.12
Hwyla-forge-1.10.8-B72_1.15.2
WAWLA-1.15.2-3.0.4

Looks like a Hwyla bug, not related to Waila Harvestability.