HomeSpan - How do I not use the "new" keyword so I can refer to the classes?

What I'm trying to achieve is this (since HomeKit has limitations):
Main LED strip controller (LED.h) that does this:
Sets brightness, hue, saturation (HSV) and sends that info to EffectClass

EffectClass sets the LED effect based on set brightness (20 - strobing, 40 - static, ...) via FastLED or some other library.