The main problem is that favorite points are not in the Groundspeak GPX schema, which is what most programs support
GSAK does support favorite points as a GSAK schema extension, so export and import back to GSAK will include favorite points. However, unless the other program supports GSAK extensions, then it is unlikely the favorite points will be populated.
GSAK does support favorite points as a GSAK schema extension, so export and import back to GSAK will include favorite points. However, unless the other program supports GSAK extensions, then it is unlikely the favorite points will be populated.