This addon is free. 

You can download it here: https://github.com/xavier150/Make-Object-Shake
I am the creator and I use this page to have more visibility on my work and for the person who wants to support me :)

This addon allows to easily make an object shake in Blender, It work with bone, camera, object, [...]
It works with Blender 2.9 and earlier versions

Objects and Camera:

• In Blender select the object you want to shake.
• Execute operator VIEW_3D > OBJECT > Make active object shake
• Now go in custom properties to edit and animate the shake influence

Bones:

• In Blender select in Pose Mode the bone you want to shake
• Execute operator VIEW_3D > POSE > Make active bone shake
• Now go in custom properties to edit and animate the shake influence

For Blender 2.7:

• In Blender select the object you want to shake,
• press Space bar for and write "Makes active object shake"
• Now go in custom properties to edit and animate the shake influence