Plotinus studied philosophy at Alexandria in the 230s, at a time when Clement’s works would have been well known among the city’s Christian scholars. Plotinus’ famous teacher, Ammonius Saccas, was either a Christian throughout his life (as believed by Eusebius) or had been raised a Christian and converted to paganism (as claimed by Porphyry). It thus is not unlikely that Plotinus encountered the Stromata in his studies. If so, could it have been from Clement that he derived the idea of using energeia as the key to his own theory of emanation?
David Bradshaw, Aristotle East and West