Inserting interpolation between animation nodes

I’m trying to emulate Overgrowth’s animation method, whereby ballistic actions like attacks are a single frame (a punch at its maximum extension, for instance), and cyclical actions like walking are two frames, legs at maximum extension and legs crossing. Fluid animation is the achieved by adding very heavy interpolation between the current state and the target animation, and massaging the curve and time to transition until the movement looks natural and biological.

Does Persona have any nodes I could use to start trying to reproduce this? If I put two single-frame animations at opposite ends of a 1D blend and blend it over time I get kind of the effect I need, but the sheer number of verbs that need to be able to interact and transition from each other seems like a bunch better fit for a state machine with some kind of intermediate node applying interpolation during transitions.