Bro, OptiFine's CEM can modify the model of the modified Creeper in "Creeper Overhaul", but EMF's CEM is not. I don't know why. I have given feedback to Creeper Overhaul's Github and they said you should solve the problem (?), so I put forward this suggestion. I really like Creeper Overhaul, but I also hope to use CEM to modify the model of the Creeper. I don't know how you think we should solve it, because this passage comes from translation software and may not be smooth. Please understand

In addition, the CEM of EMF may also affect entities that use the original renderer in some mods, but CEM should not have been effective on entities of other mods (because CEM cannot define models for entities of other mods, and of course, I may not be able to use them). After being affected, it will become chaotic due to texture mismatch with the model (although corresponding model textures can be added, many mods have similar problems that cannot be solved from the root cause). I wonder if you can separately introduce an option to prevent mods from being affected by the CEM model). Additionally, the issue I mentioned looks like

PS: This is a spider

The author of the CEM model told me about the issue with the Creeper Overhaul that it was because the original version of the Creeper Overhaul was deleted and a creature with the same name was created, which resulted in CEM not having an effect on the Creeper Overhaul. I am not sure how OptiFine solved this issue

I'm not completely sure what you are saying here and do not fully understand

EMF does allow modifying modded entities, if a pack is interacting with that strangely it is possible to modify the pack to lock the models to only work for the vanilla entities, however that may be difficult to explain given the language barrier

additonally the creeper overhaul models might now use seperate models which arent picked up as creeper.jem and instead something else

I recommend you look in the EMF settings under models > all models. and have a look around at all the detected model names used by your loaded mods and see what you can do