Example of using aframe-extras animation-mixer component with json model.
The example shows how to smoothly transion between different animation states of a character model exported from blender as json. Just hover the reticle over the shiny words to trigger different animation states.
View the working example here: Animation Controls
You can learn more about the animation-mixer created by Don McCurdy at this link: animation-mixer.
For help on learning how to get a workflow going in blender I found these two tutorials to be quite helpful.
Arturo Paracuellos has a good tutorial on how to export from blender using the THREE exporter plugin. You can find his tutorial here: Workflow: Animation from Blender to three.js.
To learn how to create and import animation actions to your character see this great little tutorial: Creating and Editing Actions