If waypoint means a viapoint, it can easily be done in the planner. Add viapoints (blue rectangle icon) and add a (local language) name.
If a nearby the track free located (poi) waypoint is meant, add a (local) name. Use the poi warning function.
https://docs.locusmap.app/doku.php?id=manual:user_guide:functions:poi_alert&s[]=poi&s[]=alert
If a nearby the track free located (poi) waypoint is meant, add a (local) name. Use the poi warning function.
https://docs.locusmap.app/doku.php?id=manual:user_guide:functions:poi_alert&s[]=poi&s[]=alert