As you note, some manual reading would be appropriate.
To answer your main question, the H8000 has two effect processors, named A and B. This limits you to two presets at a time (except for very large ones which require both A and B). Note that I said "presets" – a given preset may itself comprise multiple effects – for example, a single preset can have 8 different Pitch shifters.
So, it depends on what you are trying to do…
