Can I create an input to trigger an animation, for example, pressing a key at the right time, and then pressing the same key again at the right time to trigger another animation?
No, the node editor is here for cinematic purposes. However, you can create one common event for sequence #1 (if key at the right time), create another common event for sequence #2(if key at wrong time) and use sequence #0 that contains a conditional switching between sequence #1 and #2.
