how do I lower the frame rate of specific key frames

so I had this Idea of combining frame by frame animation with inverse kinematics.

for example, you have a slope that the player is standing on, the slope is constantly changing angles so the player's feet following the ground smoothly but when the player starts walking his legs are still moving as if they were animated frame by frame while also still going to the next point on the slope.

in short: I want a puppet rig to animate from point A to point B at a lower framerate, while also smoothly adapting to the environment.

I have been trying to figure animation for awhile trying to get this to work but I feel I have hit a wall.

any suggestions.

 

My Animancer plugin has an example which covers exactly this.