The Aromanians, according to the genetic studies conducted by Bosch et al. in 2006 regards the most possible origin of the Aromanians as in Albania or North Macedonia. Going by that study and the Greek and Thraco-Illyrian influences in their language according to the studies of Irwin L. Merker, I believe it is quite possible that the Aromanians are the romanized descendants of the Paeonians.
The Paeonians could be the explanation as to being the ancestors of both Aromanians and Megleno-Romanians. Long ago, in Antiquity, there existed Paeonia, which was the country of these people. Part of it was conquered by Macedonia and became Macedonian Paeonia, and as a result many Paeonians who lived there most likely went through the process of hellenization. Those who lived in Macedonian Paeonia probably evolved to become Megleno-Romanians.
Instead, the Aromanians are the descendants of those who remained on the other side of Paeonia, the one that remained independent. They were much more directly romanized under the Roman Empire than their cousins, the Megleno-Romanians, and there could be two explanations as to how they got so spread within the Balkan Peninsula: it was either transhumance, as most Aromanians were shepherds, or it was caused by the need of the Aromanians to flee from the way of the plundering barbarians during the Great Migration Period, time in which they settled throughout the territories of the Byzantine Empire.
Instead, the reason why Megleno-Romanians spread is not clear since they were agriculturalists, unlike the Aromanians, but the Ottoman Empire was definitely a contributing factor. Whilst their existence in Greece and North Macedonia is explainable, the fact they are in places such as Romania, Turkey and Serbia, far away from the territory of Macedonian Paeonia, raises several questions. However, these communities outside of Greece and North Macedonia are quite small, so they could have been the descendants of Ottoman janissaries, since all of these were areas near the borders of the Ottoman Empire, which could also explain why many of them are Muslim.
So, in conclusion, the Aromanians and Megleno-Romanians are the descendants of romanized Paeonians. However, the main difference between them is the fact that the Aromanians were romanized stronger than the Megleno-Romanians, who also went through a process of hellenization. But, a couple of Aromanians in Epirus did go through the process of hellenization, gaining the name sărăcăciani.
