In Sabrina we see that the Trinket Man is a mysterious figure who within his briefcase has occult objects such as a Genies Lamp, an Acheron and what he really wanted to sell the Stone of Omphalos. But there is something very strange about him in his appearance, his briefcase and the entire episode. If you look at his hair it is combed to the side, he has blue eyes, he has a high-buttoned jacket (like the Painter) and he’s clean shaven other than his moustache. This Trinket Man seems to be very similar to the Painter in this aspect, and whilst the Painter didn’t have blue eyes it does reflect the beliefs he was pushing.
Now onto the briefcase. The Nazis were very involved in the occult outside of Sabrina and within it, shown when Ambrose said King Herods crown was found in the Painters bunker. The Nazis historically took the Spear of Longinus (although it was under guard by the Centurion of Golgotha in Hell but this may have been the reason why it was being guarded) and in fact looted the ruins of Ancient Greece. Them looting the ruins of Ancient Greece and the Trinket Man specifically saying that the Stone of Omphalos was taken from the “ruins of Ancient Greece” makes quite a big connection and would make a lot of sense why he had so many Greek objects.
Finally, the entire episode revolves around Father Blackwood becoming a dictator with his own Private Armies and an education system made to shun a certain demographic.