I feel like I missed something and should already know why this is crashing, but I figure the crash can at least be documented here. Thanks for all your hard work!
I'm trying to run the Life in the Village modpack created by xDreamz and managed through the Twitch app. I chucked the latest Replay Mod release for Minecraft 1.12.2 into the mods folds, hit play, and then hit play on the launcher. A couple of seconds later the launcher comes back reporting a crash.
I'm not looking for a fix but would appreciate one if it does come around.
Life in the Vallage-1.13
One of the coremods which you've got installed is broken. It (probably) works fine on its own but does something which it must not do (in this case early loading of Minecraft classes) which then breaks stuff further on in other mods.
I've looked through your logs but none of the coremods listed raise a flag, so you'll have to remove other mods until you find the one at fault.
Be aware though that due to the nature of these kind of bugs, innocent third-party mods may still need to be present for it to actually crash. See e.g. this issue where p455w0rd's lib is at fault but the crash will only happen if either BetterPortals or LagGoggles+VoxelMaps needs to be installed (none of which are actually at fault).
Thank you for the informative post!
I began, as you said, testing each mod by removing them one at a time and then testing the client. The client fully launched once RandomPatches [randompatches-1.12.2-184.108.40.206.jar] was removed from the mods folder. After reinstating the previously removed mods besides RandomPatches, the client still launched fully.
I'll try exploring some elements of Replay Mod while I consider what to do next with this information.