Two different routes, two different documents
The E-2 route needs a bachelor's degree and treats Australia the same as the US, Canada, UK, Ireland, New Zealand and South Africa as a core native-speaker country. The working holiday route doesn't require a degree at all, since it's a general reciprocal visa rather than a teaching-specific one — see the dedicated working holiday page for how that visa works and what it does and doesn't allow.
Most Australians who want a proper teaching contract with housing support and a set salary go the E-2 route; the working holiday visa suits people who want flexibility and are open to a mix of casual jobs, one of which might be tutoring or an informal teaching gig, though formal hagwon employment on a working holiday visa needs its own check with the employer.
