Include HERE Maps Flexible Polyline as format much like the Encoded Polyline is included in the Geometry Encoding.
Documentation can be found here: https://github.com/heremaps/flexible-polyline
Unfortunately HERE Maps uses another type of encoded polyline as a variation from the standard.
This would be great to make API requests and return their version of the polyline, and feed directly into Geometry Replacer to create the Geometry.