Thank you for your interest in 3D support for the spine-godot runtime! Unfortunately, I don't have any new updates to share on this front.
As you've noted, the spine-godot runtime currently only supports 2D SpineSprites. 3D support has been a highly requested feature, and there is an open issue tracking it:
https://github.com/EsotericSoftware/spine-runtimes/issues/2135
Due to the technical challenges involved, 3D support has not yet been scheduled for implementation in the near future. In the meantime, the community has proposed some workarounds using the current 2D functionality, which you can find discussed in that issue thread.
We understand this is a pain point for many users, and your feedback and interest in this feature is appreciated. Keeping an eye on the GitHub issue linked above is the best way to stay informed of any progress or updates as they happen.