How to configure visemes for multiple meshes?

Hello!! I’m completely new to creating skins, and I have this character whose face gets really deformed when talking. I wanted to know how to transfer the facial movement to a mask or any other accessory that I can put on the head, since I understand that you can only apply the mouth movement settings to the main mesh. This is all within Unity, of course. The mask already has blendshapes, but the problem is configuring it within Unity.