poopoodice

RegistryObject is an extension of java.util.function.Supplier

You can change item model through ItemPropertyOverrides https://mcforge.readthedocs.io/en/latest/models/overrides/, like bows...etc.

You also need to override isCrossbow in your item class.

The text being displayed and its action are separated therefore you can just create a new style with click event (Style#setClickEvent), and then use TextComponent#setStyle to assign the style to the text.

You can either change the field type to EntityType<?> or you have to manually cast the entity type (which eventually you're gonna cast is somewhere else).

Show your model class.

Please always provide the crash log. You should not register anything through Vanilla Registry (see the comment above the class), use the deferred register that you already have.

Players can't eat food when they are full, but you should be able to change it through the food builder.

My think is since an ImageButton renders an image on it, if it renders text as well it will become really messy (mixture of text and image). For every widget to have a message/title is probably for voice narrating? I'm not so sure about this.

Please provide the crash log, and you should probably get the block colours from the event instead of minecraft instance.

The constructor of both of the button you are using passes Button.field_238486_s_ (empty), whereas there won't be any hovered text/tooltip being displayed, so I assume you are talking about the text that is rendered on the button: ImageButton overrides renderButton and does not call super.renderButton(...) (but Button did), and in Widged#renderButton it draws the title you passed in, therefore ImageButton does not render the title, but Button does.

It looked right, for me at least.

LivingHurtEvent only triggers when a living is being attacked, where you can recalculate the corresponding damage when the attacker is holding your sword. If you want to change sword texture based on the time, check out ItemModelProperties, the provider has world as one of its parameter which you can also apply the game time logic there as well.

You can use LivingHurtEvent and check if the attacker (DamageSource#getTrueSource, it can be null) is holding the sword, then modify the damage according to the time (World#getDayTime or something) there. Or you can override Item#getAttributeModifers and apply the calculations there.

What's the condition of changing the texts? If it's your own screen I think Screen#tick might be what are you looking for.