Hey, This is a bug. The blenshape animation does exist on the skeleton. It just needs to be invoked. Simply bypassing the skeleton blend in the unpack character will fix it. This is being fixed 🙂
Here is a basic slider setup.
Attachments in this post:
http://fx-td.com/houdiniandchill/wp-content/uploads/discord/20250712/03/25/image.png
http://fx-td.com/houdiniandchill/wp-content/uploads/discord/20250712/03/25/apex_rig_to_solaris_as_usdskel_plus_blendshapes.hiplc
http://fx-td.com/houdiniandchill/wp-content/uploads/discord/20250712/03/25/output.gif
http://fx-td.com/houdiniandchill/wp-content/uploads/discord/20250712/03/25/mouth.zip