Hi and thank you for your interest!
I honestly don't have a list of tropes I refer to and I can understand if people are skeptical about what they can submit and what they can't. Please don't stress too much about what is acceptable and what is not I really just want people to try make some cool games using RPG Maker with some out of the box thinking.
You mentioned TTRPG in your post, I'm not sure on if that's the type of game you plan on making, but they are fine since the main element of it is the Tabletop part of the RPG and would be perfectly fine for the jam.
Even if you were - for example - to submit your game as a horror but in actuality it was just an RPG with some random zombie graphics thrown in, I'd be perfectly OK with that. The bottom line is I just don't want to see any bad anime fangame type Final Fantasy/Dragon Quest clones here.
For the record I am looking forward to playing and trying out every submission here, so you would really have to go out of your way and purposely troll me or something for the game not to be acceptable for the jam.
I'm sorry I can't be more specific on the rules but it's so difficult because I think 90% of games even outside the genre have some sort of mechanic/concept of an RPG.
If you have any further questions or need an answer on something specific please reach out again.