>>371673481
I often use the bone method but setting it as a mesh is pretty good option too if you have free mesh slots.

The bone method kinda gives you more control over the animation and allows you to use dynamic bones when compared to pure blend shapes. You just need to scale the bones down in Blender before export and animate them to scale up when you toggle them so that people who have your animations off won't have them enabled by default.

Blend shapes are a bit easier for simple cases since you can have them scaled down by default and exporting is smoother.

Skinned meshes give you more control but there's only so many you can use before you become very poor... As a side note can you use a non-skinned mesh with a constraint or script or something to get around this?