Just like Grid Fill in Blender or Quad Fill in Modo.
For a proof-of-concept maxscript implementation see Border Fill (unencrypted), and multiple others like RapidTools RapidQCap, RappaTools autoConnectBridge or Quad Cap Pro (doesn't use the curvature IIRC but identical with planar meshes).
All of them are maxscript tools and as such bound to be slow with complex meshes, plus they don't fit in the rest of UI. Having a native version would be great.