Beelzebub is a specific case as in the ancient Philistine language that just means 'lord of that which flies'. In Hebrew this was corrupted by meaning to mean 'lord of the flies' despite the same basic sound.
Other Goetic names like Ipos are just linguistic evolutions of Coptic Egyptian words, for example Anubis real name is Inapaw which became Ipos, but the enemy did rely on this name to hide the fact this was Anubis because Ancient Egyptian became indecipherable after a point.
We do not call Astarte, for example, 'Astoreth' (shit, shame in Hebrew) or 'Mary/Maria' (corruption of Meri, one of Her names) because that is a grotesque insult to Her.
Some descriptions indicate which names the Gods highly prefer to be called by.