Galactic Ambitions Research, Stellaris Starchart Trade, Survey, Anomaly

Is Anomaly only generated while surveying planets? If so, trading starchart (and Galactic Ambitions research) would be detrimental to solve some quest, let's say, like Cybrex one..

Solution 1:

Anomalies are unique to every player, i.e you can find an anomaly in a system another empire already surveyed.

However trading star charts automatically surveys the system for you permanently, this means, you can no longer survey it and any possible anomalies in there can no longer be discovered.

Galactic ambitions works different, it surveys systems temporarily as long as they are controlled by another empire. If you conquer the territory the system is no longer surveyed and can be scanned by your science ships.

So, in conclusion, if you want to avoid missing anomalies, never trade star charts, galactic ambitions is ok, unless you want to play pacifist, then you probably should not take it and survey systems in other empires by acquiring civilian access instead of conquering them.

source: personal experience