It should be possible to export GXP eXchange files (*.gpx) to a Garmin MapSource GPS format (*.gdb) with popular programs like the GPSBabel or similar.
Convert GPS eXchange format to Garmin MapSource GPS waypoint database.
We found 5 software records in the database related to .gpx to .gdb file format conversion.
Microsoft Windows software - convert gpx to gdb on Windows
A navigation software used to plan and organize trips
Convert from gpx file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned gpx to gdb. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Program for converting waypoint and GPS map formats
Apple macOS / Mac OS X software - convert gpx to gdb on OS X
Application that allows users to convert waypoints and GPS map formats.
Linux/Unix software - convert gpx to gdb on Linux
Program for Linux that allows users to covnert waypoints, tracks, and routes between popular GPS receivers.
On-line services software - convert gpx to gdb on web
A GPS mapping tool