So to info dump on this post about a topic I feel like a broken record about:
Yes, Kunikida's ability 独歩吟客 (Doppo Ginkaku | ENG: The Matchless Poet) is taken directly from a pen name the IRL Kunikida went by. This is confirmed from the first guidebook from the anime where it says
能力名の「独歩吟客」はいくつもある独歩のペンネームのーつ
"The ability name 'Doppo Ginkaku' comes from one of Doppo's many pen names"
The Author Guide at the end of BSD manga vol. 3 also says this about his ability:
"The skill The Matchless Poet does not refer to any specific work, but is based on his naturalist writing–a style that emphasizes accurate depiction of details."
With those two pieces of information, I'd argue that Kunikida's ability is more based on the IRL Kunikida himself, rather than inspired by a specific piece of work like other abilities are.
And yes, Ranpo's "Super Deduction" is not a reference to a specific piece of literature, and AFAIK Lovecraft "Ability" is the same way. I'm not a big Lovecraft person, but an irl friend of mine who is a lot more familiar with his works agreed that BSD Lovecraft's "The Great Old One" isn't a specific literary reference either as "The Great Old Ones" is something that exists across multiple of his works.
If that is true then there starts to become a pattern: abilities that aren't abilities at all use the lack of specific literary references to foreshadow that.
We do know that The Matchless Poet is an ability as No Longer Human can nullify it, but I feel like there much is more to it that we currently don't know. (Also the discussion of whether or not The Book is an ability, most people say it isn't but I personally believe it very well could be at least connected to abilities... like a singularity rather than a normal ability)
Also to that last part, Kunikida also gave Kyouka 2 pages from his notebook
They are folded up so we can't see if anything is pre-written on there, but given the context of their conversation and also what she summoned with the pages I am extremely inclined to believe the pages were blank. I love Kuni-kun but there is no way I'd believe he had the foresight to know that Kyouka would need glue + putty to hide in the vents with Atsushi, especially after he told her that there is nowhere for them to hide.
Which creates an interesting implication that anyone can write something in his notebook for him to create.
