I'm working on the code in the 4.26 environment.
Your
'SekiroHooKPJCharacter.h'에서
FORCEINLINE const FTransform& KunaiIdleSocketTransform() const
{
return GetMesh()->GetSocketTransform("Idle_Kunai_Socket");
}
FORCEINLINE const FTransform& KunaiSwingSocketTransform() const
{
return GetMesh()->GetSocketTransform("Swing_Kunai_Socket");
}
This part probably returns Null.

also
HookeablePointWidget에서
"Widget" is declared Private.
How did you manage to cast?
wbp_tracker_ = Cast(Widget);

I can't come up with an idea.

I'm sorry to bother you. I am leaving an Issue because I think it will be very helpful to your code if you check it once.
I studey your code and 'https://www.mattiacasamenti.com/nim.html#accordion2''
I got a lot of help by studying the code below together.

I'm afraid that I might ask the wrong question because of my poor coding skills, and please understand that my English is not the main language, so I'm not good at English.