Registering Styles - GiantLuigi4/StylesPlusPlus GitHub Wiki

Styles++ uses a reloadable style registry, so you don't actually register a style, you instead register a function which registers your styles
To do this, you just call StyleRegistry$addStyleLoader with a runnable which calls StyleRegistry$register once for each of your custom styles

		StyleRegistry.addStyleLoader(()->{
			StyleRegistry.register(new Identifier("stylesplusplus:wavy"), WavyStyle::new);
		});