I've been doing some thinking about Privaron!Nemo and I think I've sort of partially come up with a proto-idea for an Advanced Skill for her to have.
Brujeria is hollow Kido. Kido is "pure". Practitioners use spirit energy and maybe some objects to achieve a number of effects. By comparison, Brujeria seems to be "impure". Practitioners also use spirit energy, but pair it with some kind of connection to living people, such as blood or an incantation which references a living person. It's not pure spirit energy molded into a spell. Kido's incantations don't involve or invoke people, they're just "empty" poems.
Maraña is hollow Reiraku. There are two primary differences between them. The first is that Maraña can only be used to make apparel whereas Reiraku is basically anything to do with cloth, including cloth soldiers. (Which Maraña can't make because you can't wear them.) The other primary difference is that Reiraku doesn't use reagents whereas Maraña requires them. Unlike the other limitation, this may have an upside, in that the usage of reagents makes it easier - or possible at all - to imbue items with certain effects. Reiraku can't grant someone Senescencia, to my knowledge, but Maraña definitely can.
My guess as to what Privaron!Nemo would have is, in fact, a hollow version of the Name stuff Ichibei has, where instead of dealing with names, the practitioners instead deals with words. Specifically, words of power. Nemo - both versions - are rarely shown to explicitly speak, are only shown doing so when saying something important, and their speech text is always coloured, even when not releasing despite coloured text speech only occurring for others when releasing. Explicit speech is already narratively important for the two Nemos, so it wouldn't be a stretch to make it mechanically important for the Privaron. When she says a word of power - something that would necessarily have to be rare both mechanically and narratively - a significant effect happens. (An example that comes to mind is
this.)
There are a lot of holes in this idea. It doesn't have the same "connection" requirement that the other kinds of hollow magic require which needs solving, but on the other hand maybe it doesn't. The exact mechanics behind it would have to discourage spam and be natural enough that it wouldn't feel like a forced limitation. There'd also have to be some way to teach it, since this is something Minirucci would probably learn under her. There are probably other holes that I'm not thinking of, but I think it has potential.
fakedit: Hollow energy is naturally corrosive to pretty much everything, which is why Gran Rey Cero - which has so much of it concentrated together - distorts space. Maybe Privaron!Nemo's thing works by taking advantage of that fact. Trying to spam it would be like trying to break an already broken plate - ineffectual and pointless. Reality needs to heal before you can damage it again.
Um... she's still missing the cloak.
