How to make freckles move naturally on the face

So I’m making a little dancing animation where my character will change facial expressions.

However, my character has freckles and I have no idea how to have the freckles follow the facial features (aka distort it in a way that will look natural)

I figured out I can use skeleton deformation, but I’m sure there is a simpler way. Having to realign every child bone whenever I moove a parent bone is annoying lol

Must to be by morphing, or can be switch from a library? Some like this one: