that won’t really work
the blender face rig is bones
the live link system is based on ARKit
ARKit doesn’t use bones
it uses a set of 52 or so blend shapes
so you need to make facial expressions using sculpting and create blend shapes to match the arkit set.
in blender you can enable MB-Labs and if you make a char you can apply phonemes and expressions, which might get you closer to what you are trying
metahumans are arkit enabled so they have the full set of expressions for arkit.