Hello @Sulenor, maybe not exactly what you‘re looking for, as the SimConnect API (still?) does not give access to actual „multiplayer“ aircraft instances (the same reason for which you e.g. don‘t see multiplayer aircraft in Little Navmap).
But the latest Sky Dolly v0.16 release offers extended flight import/export plugins, with automated time synchronisation functionality based on real-world timestamps (*).
So essentially:
- Every multiplayer records her flight
- One pilot collects all exported flights and imports them all at once into a single „formation flight“
- With optional automated timestamp synchronisation
(*) And yes, with proper timezone support
For more details also refer to: