It must be a plugin, Mesh+, Chromodoris …
https://rhino.github.io/components/meshplus/meshLoft.html
Here’s a custom mesh loft component that I developed some time ago in Python. I use it quite frequently. It’s only meant to work with polylines though.
Feel free to check it out:
Mesh Loft .ghuser (5.6 KB)
If you put it inside your user objects folder, it will appear in the Grasshopper Mesh menu.
Update
Here’s an example:
mesh_loft_example.gh (19.3 KB)
Mesh tools is a Plug-in originally developed by Mateusz that you can find here, his implemetations are very fast and a few have been directly added from it directly to Rhinocommon (like mesh pipe): https://www.grasshopper3d.com/photo/mesh-tools
