The main difference between Hype and Greensock is that Hype is a visual tool and Greensock is a code-based tool. This means that with Hype, you can create animations without having to write any code, while with Greensock, you will need to write code to create your animations.
Greensock animations are generally more lightweight and faster to load than Hype animations, since Hype animations tend to be more complex and use more resources. However, this is not always the case, and it really depends on the specific animation.
You can run animations from both Hype and Greensock on a WordPress page, but it really depends on what you are trying to achieve. If you want to create more complex animations, Hype may be a better option, but if you want to create more lightweight animations, Greensock may be a better option.
Hype uses absolute positioning to create its animations, which means that the position of each element is determined when the animation is played. Greensock, on the other hand, uses any positioning, which means that the position of each element is determined based on its position in the code.
Motion.page is cool and I also use it on WordPress projects, but if you need something platform-agnostic using GSAP the Spirit extension comes in handy:
Another tool being developed in Berlin you should keep on your radar is …
They have been funded with 2 Million recently and are open source
Given you are a designer, Tumult Hype is a good choice and the learning curve is rather small if you stick to its capabilities. It solves most problems, but it certainly isn't the tool of choice when it comes to animated existing HTML outputted by WordPress.