The claim that Hegel stands in any line at the start of which is Plotinus looks highly suspect to me.
I make just two points. In the first place, Hegel's Absolute or God, or One if one chooses that terminology, has an inescapably historical dimension. The Absolute develops through time, seeking ever more adequate modes of expression and embodiment, ever more adequate concepts and modes of knowledge through which it can be understood in and by the expanding self-consciousness of human beings - which is also its own self-consciousness. Whatever one makes of this, nothing like it could be remotely true of the One of Plotinus. Plotinus' One has no such historical dimension. It is, and eternally is what it is. It cannot undergo the historical development by which Hegel's Absolute unfolds in time. The perspective is quite different.
Secondly, in the Absolute Hegel had to reconcile infinity and personality. The Absolute is not a person but it is present in and known to persons; and these persons, with their capacity for self-consciousness, are manifestations of the Absolute - and necessary, not merely contingent, manifestations.
Plotinus's view of the relation of persons, or souls (psuches), to the One is quite different. The One is that perfect excellence with which the soul, in some way alienated, must reintegrate itself. It must return to the One and do so by its own efforts. Rist refers to :
confidence, based on personal mystical experience, that a return
to the sources of the soul, to Nous and to One, is possible for
every soul. For such a return to excellence is possible in
Plotinus, as in Plato, by the soul's own efforts. The soul needs
no further help from the One, or from Gods or saviours (III,
2, 8-9) to enable it to return, for it has been generated from
eternity with the necessary powers within itself. Yet although
Plato, like Plotinus, thinks that man can be "saved" by his
own efforts, he fails to make clear on what psychological theory
such a doctrine is based. In Plotinus, however, the psychological
theory is made explicit: it is the theory of the undescended part
of the soul. (John M. Rist, 'Integration and the Undescended Soul in Plotinus', The American Journal of Philology, Vol. 88, No. 4 (Oct., 1967), pp. 410-422 : 417.)
Hegel can accommodate no such view. Persons are not 'declensions' from the Absolute to which by some means they must return. Rather, they are products or manifestations of the historically developing Absolute. The rough picture is that the Absolute must in the temporal process express itself in persons, in self-conscious minds. They are a phase of its development; this is radically different from Plotinus' idea of the One as an already existing perfection from which human souls, psuches, persons, have managed to alienate themselves and with which they must reintegrate.