I'm into Photography as one of my hobbies, but the curse of using a Sony camera is that they don't have GPS built into their bodies. On top of that, their app which is supposed to connect to your camera via bluetooth sucks, and often loses connection randomly (or doesn't get a connection at all) leaving many, or all, photos without GPS data.
Right now, Ive been using 'Geotag Photos 2' which records GPS location data, sends it to their server, then lets you download/tag your photos from a 'trip' with GPS data.
Obviously, I hate that.
I know of OwnTracks, but I don't believe it offers any way to export data to a GPX file for tagging photos with.
I have Home Assistant accessible from the outside, which tracks location, but I don't believe it can be exported to a GPX and I don't believe it records location if it can't "phone home". If Im out on a hike, that would interrupt service and kill the usage of it.
If the app just records data, and doesn't send it to any server, I can live with that - I just want something fully local that isn't sending my location to any companies servers.
I use Osmand (offline-capable maps app powered by openstreetmap) - it allows you to record a journey and saves them in GPX format
It may not the best option here though IMO as it is a navigation app, and might require some minor customization to make it easier to use for this purpose