Two faces are split by an imprinted line. Integrate a new surface to an existing face using a birail. The surface interpolates the birails and the new surface can be added and connected to the given part. Working with a lower resolution (1e-3 or 1e-4 mm) will help to keep the data size of the surface low.

Birail (white) is the imprinted line. Spine (orange) is the face edge.

Profile swept along the spine which was scaled and rotated to fit the profile