I wanted to install Fresh Moves which obviously requires EMF/ETF and found out that it crashes on startup.

"The game crashed: initializing game
Error: org.spongepowered.asm.mixin.transformer.throwables.MixinTransformerError: An unexpected critical error was encountered"

crash log

• Minecraft version: 1.20.1
• ModLoader: forge
• ETF Version 6.2.9

I guess i should pin one of these...

yes this mod does not work with optifine, it is an alternative to an OptiFine feature (Custom Entity Models) that also expands on the concept with things like player and armor models

There are plenty of alternative mods including this for all the OptiFine features you may want:

• Check out this list
• or get the Fabulously Optimized modpack that has it all