Trust me, we were all beginners at one point or another. And, hell, there are some writers who are goddamn terrible at the 'writing' part, yet still hit it big. Of particular note- JK Rowling. Say what you will- her technical skill is garbage, and she is indisputably successful.
- "I mean could Marvel really sue any one else that wanted to use a word?"
They can, and they have. Specifically, Marvel and DC co-own a trademark over the word 'Superhero', and there's been at least one lawsuit against a small publisher using that term. The message is clear: they can and will protect these words as part of their IPs.
And Marvel, specifically, has weird legal issues over the ownership of some of their characters. Long story short (because I'm not qualified to delve into the 'long' part), it's why Scarlet Witch is a mutant in some continuities, and an actual magic user in others. Because different studios own the character, but only one can use the word 'Mutant'.
... Now, because of how copyright and trademark work, you've got room enough to use 'Mutant' in other mediums. After all, mutations are a scientific term (and essentially owned by nobody), so you're generally safe in other scifi worlds. But when it comes to the superhero genre... mind you, I am not a lawyer, so take my advice with a grain of salt... but if Hollywood juggernauts aren't willing to tread these grounds, you probably shouldn't, either.
- "Something like Imbued would be nice but I can't tell how you found that obscure word or what would work for me."
I have a large vocabulary. It helps that Imbued is something of a synonym to "gifted" as well as having less pleasant implications like "injected" and neutral ones like "permeate".
- "I'm thinking about going with Hallow(s) or Hallowed(s) What do you think?"
Hmm... might me a little too spiritual a concept. I'm not saying there won't be people who use it- in fact, it would be a great "archaic" term for them (and I wish I'd thought of it because I'd totally use it- or maybe I'll use 'sanctified'- yeah, that sounds good)... but the "modern scientific world" would probably want to call them something that doesn't have religious connotations.
It'd be interesting if they called *themselves* Hallowed, while normal society used a less flattering term. Which is kinda what Marvel did, with "Mutant" vs the much more pretentious "Children of the Atom".
I'm not sure what official terminology would pop up in your world, but I think any bureaucracy would default to technical language.