Ender Zoo adds Dirt Slimes which have a chance to spawn when dirt is broken without a shovel, PSI break block sequence causes them to spawn as if you was breaking it without a shovel.

I mean you are breaking it without a shovel :p

The fix for this would be "make break block look like a shovel to everything" which is not suitable imo

Unless I'm misremembering, that's actually how the mod author wants things to be compatible with the dirt slimes, strangely enough.

Maybe Break Block could look like a shovel to just dirt, or maybe look like all tools to all blocks? I dunno.

You could simply disable the Ender Zoo Khendrel Keght, Chryseus. They're called Dire Slimes in the config, I believe.

Well the main point of dirt slimes in the first place seems to be to discourage breaking dirt with hands, PSI is clearly not equivalent to hands so it doesn't really make sense to have them spawn, I know they can be turned off which I've done on my own server but that's more of a quick fix than an actual solution.