I’m not sure if this a bug or intended, but the skeletons summoned from Mortacrux do not seem to count as minions for the purposes of of the requiem aspect. IIRC they did count in the PTR and I think (though not sure) they did in the live 2.0 game initially, though that may be wrong.
In addition to the mentioned aspect interaction (or rather non-interaction), I wonder if the Mortacrux-summoned skeleton’s even count as minions at all, e.g. for the Shademist aspect or for the Kalan’s Edict key passive
No where on the item does it state the effect of the unique is a minion, its called a “Simulacrum” and i wouldnt count that as a minion, so without even testing this i can say that it most likely dont count as a minion, at all, since it isnt one.
If wording would be so important, many aspects, items and skills should affect neither skeletons nor golems, apart from the Skirmishers warrior type, as only the latter’s description contains the word “minion”. Both Raise Skeleton and Golem are Summoning skills, based on their tag, but they don’t classify the summoned beings as “Minions” in any way 
Raise Skeleton mentions that Skeletal Priests empower “Minions”, but that also doesn’t necessarily clarify the classification
So, the question lingers: Are Skeletal Simulacrums “Minions”, similar to Skeletal Warriors and Skeletal Mages seemingly being “Minions”, and should matching aspects, items and skills affect them as well?
Sure, but there are other interactions where they do count. For example, they seem to count as minions for the purposes of the Great Feast aspect. So if you are running a build where you do not have any other minions, except those coming from Mortacrux, you will still fail to get the damage bonus.