Skill extension must apply skill patches.
With FE8J, there is aera's FE8N.
With FE8U, there is circleseverywhere's SkillSystems.
FE8CN is a Chinese translation of FE8J, so it is for FE8N.
However, although it is very disappointing, I have not yet separated the skill patches.
To say for both FE8N and SkillSystems,
Since skill extension patches rewrite various areas in order to realize skills, they could not easily be separated like magical CSASystem.
In addition, badly, FE8N includes extensions other than skill extensions, so it can not take simple differences.
Likewise, SkillSystems also has a BossRush stage for confirmation and so on, and here also we can not make a simple difference.
I think that it will become possible to install with one click if it can extract the skill extension part and package of the patch can be done.
This will be a future subject ...