The thing is is that we have told you multiple times what you need to do, but you keep doing things that don't make sense in java and/or refuse to do what we tell you to do.
For example, you're still trying to call Item.registerItems, even though I told you that this was reserved for minecraft's items and you should never ever ever call this yourself, and you should not even have it imported. This is what is resulting in your crash.
Example two, you still haven't made your registry method static.
Also, you need to annotate the method with SubscribeEvent, else the method won't be called (you should also not be calling it manually, in case you were thinking you should).