Log: https://hastebin.com/tihohuvaci.md
Mod Version: 2.0.1
Forge Version: 14.23.5.2854

There is certainly a mod in there that is causing a conflict, but I can't determine what it is from the log. Unless you can narrow it down by removing mods until there is just the culprits, there isn't much I can do at the moment. If you don't want to do that I understand, if you add "thecodex6824.thaumicaugmentation.core.transformer.TransformerHarnessSprintCheck" to the "DisabledTransformers" list in the config you should be able to stop the crashing, but this isn't a proper fix.

I found that the issue was between this mod and an unreleased 1.12.2 mod called PlayerAPI which is used for SmartMoving mod.

That would explain why I had no luck figuring it out. Seems like there's multiple versions of PlayerAPI floating around the internet, are you using the Player API 2019 one?

Edit: I just tried it and had the same crash (and another one after I fixed that), should be fixed now

Oh I see you fixed it, but just to make sure, it was this version I was using
PlayerAPI.zip