This becomes important when a spell such as Simulacrum or True Polymorph, or any other shapechanging spell that affects equipment, is cast.
Say I make a Simulacrum of an orc, let's call him Simulacr-Orc, that is armed with an axe and the orc has a Haste spell on it. The spell says that the copy won't have any equipment. So, no axe for Simulacr-Orc. But does Simulacr-Orc gets a Haste spell on itself?
And what about permanent magical effects instead? While the rules don't say much about how a permanent magical effect might exist on a creature, let's suppose that there is such an effect. Something happened to that orc in the past, we have no idea what, except that this orc now has a permanent Haste spell on it. The source of the magical effect, how exactly that happened, is not important here, only the magical effect, in the same way that when a delivery truck brings you a package, it is the nature and content of the package that is important, not the color or size of the delivery truck. So, will Simulacr-Orc also get the same permanent Haste magic on itself? Or a non-permanent Haste magic? Or no Haste magic whatsoever?
After all, creating a permanent magical Haste effect is pretty much like the equivalent of creating a magical item, like, say, some kinds of Boots of Haste. And with Simulacrum, items, magical or not, don't get copied over, right? Our orc's "permanent" Haste would be akin to the orc owning fully invisible, intangible, Boots of Haste, that he doesn't need to wear on his feet to use, that doesn't prevent other boots on his feets, and that also don't need to even be inside his equipment at all. Kind of like I'm here, and I own 1000$, but that 100$ ain't on me, it's in my bank account, and yet I still own it and can I still use it. So, yeah, permanent Haste on orc: will Simulacr-Orc get something or what?
What about some past event (whatever it is) that magically modified our orc, in an instantaneous way. Instantaneous is like how a Fireball is an instantaneous spell, that does it's damage, but then after the spell is fully gone, the damage remains and is still there. Similarly, that mysterious magical event came and modified the orc. Our orc instantaneously gained both a +2 bonus to Strength, and a +2 ability increase to Strength. So, would Simulacr-Orc also gain those benefits? Only one? And then, which one? Or none?
In short: Are magical effects copied over, and, if yes, which ones (aka "to what degree")?
Basically, anything in the RAW rules supporting either interpretation?
Thanks!