After downloading v2.0, I've been unable to load into a world without crashing.
crash-2020-07-26_17.52.46-client.txt

The crash log you gave me shows the game crashing in something ASMC is doing. However, I just booted up a pack with my mod and ASMC and everything worked fine, so something odd is happening. Maybe try disabling the coremod in the Thaumic Augmentation config, and see if that helps?

Nope, it's still crashing after I disabled the coremod. Also, it was originally crashing and was saying it had something to do with Better Diving so I removed that and it was still crashing and that's when I sent that log where it said it had something to do with ASMC, which I also removed and it still crashed. I guess I'm just gonna have to do the good ol' add 10 mods at a time until it crashes.

This is going to sound weird, but I think the problems are that the "Disable coremod" toggle doesn't work, and my coremod conflicts with colytra. Removing that might work for now, but either way there will be a hotfix ASAP.

So I didn't get very far because I just loaded it with Baubles, Thaumcraft, and Thaum Augmentation and it's still crashing when it's loading a world.
crash-2020-07-26_20.26.30-client.txt

i also got the crash with just thaumic augmentations and it's dependencies on world creation https://gist.github.com/lag42/5a49af235e19149095dcda440a1d5162
specific versions:
baubles: 1.12-1.5.2
thaumcraft: 1.12.2-6.1.BETA26
thaumic augmentation: 1.12.2-2.0.0
forge: 14.23.5.2854

Yeah that's a different crash that was just me being stupid, I'm in the process of getting a hotfix ready to publish to Curse

Once it's done processing / approved the hotfix is here. Sorry for the trouble everyone!