Your observation is correct. The current situation is:
- Standard character: standard 60 facial blendshapes and custom blendshapes are available after export
- Game base: only standard 60 facial blendshapes are kept after export
- Remeshed (LOD character): N/A
The remeshed characters are defined to be used in background, so no facial morph will be supported.
Because of the nature of remeshing technique, it might be difficult to achieve what you expect.
However, it might be feasible to support exporting custom blendshapes for game base character. May you submit this request to Feedback Tracker?https://www.reallusion.com/FeedBackTracker/
It helps us to track issue and prioritize the feedback from users. Thank you!