I shall reiterate the issue I was having, this time with a client.log to show for it and a modlist. Certain Enchantments aren't working properly... only NPC Contact Angler does from what little I tested of it. The specific Enchantments I was attempting to apply were Attack Speed and Size. Even after I reduced my mod list to just Koko Net Lib, Weapon Enchantments, and Archery Overhaul (the mod where the main weapon I was attempting to enchant came from), I continued to have the issue. The weapon I was attempting to enchant was called Dual Shot, I think.

Once More, But Not Buried In Bug Description: The bare minimum modlist was Koko Net Lib, Weapon Enchantments, and Archery Overhaul (...And Shop Quotes, on accident.)

Here's a pastebin containing my ENTIRE client.log for a session where I log in, fire the bow a couple times with and without enchantments, and then log out: https://pastebin.com/eTaQUJ61

Something I noticed skimming the thing over is that the logs mention various Thorium items even after having disabled Thorium entirely. Granted, I had unloaded items in my inventory from Thorium among other mods, but many, if not all, of these mentioned items weren't in there at all. I have no idea how relevant that will be to helping troubleshoot the case, but it's definitely something even I, someone with no coding knowledge whatsoever, thinks is a little bit strange.

Sorry for taking so long to get the client.log and the modlist, life had me busy. Sorry for the hassle, I know these kinds of things are a pain in the neck to deal with. This mod was working just fine before, and I love it lots! I wish you luck in the endeavor of troubleshooting.