First things first, aren't unauthorized remakes a copyright violation? I mean, they for sure aren't unless the copyright holder doesn't care, but still. If someone's remake goes big, there is a chance of the developer getting in trouble, I suppose. I would like to take part in your jam but the whole copyright mess has kind of puzzled me for quite some time. Any insights on this topic?

Well, I just saw the description of your jam and it says "to explore the concepts of existing classic titles", so, in my understanding, it isn't supposed to be a remake (like RE remakes) per se, but something that's more like a "title"-inspired game (or maybe like rogue-likes or souls-likes)? What can be taken from the original? Just the concept or some gameplay mechanics or the entire plot with characters etc.? I'm a bit confused here as well, please help!!

I'm personally okay with any of the possibilities btw. Just would like a little clarification!!

Right. The idea here isn't to create something that directly in direct conflict with existing trademarks, but to allow people the opportunity to explore the mechanics of titles that may have inspired them to get into game development. I am not a lawyer, so this is not legal advice, but as far as I'm aware legal troubles for people mostly start when someone begins to charge money for their product, using IP that is directly owned by another company. It would be my advice that anyone who hopes to make it big or make money off of their product, avoid the use of assets and trademarks that are not freely available to the public, or owned by existing entities.

I mean if you're comfortable making a game around a licensed character go for it. I'm not a lawyer so I can't advise you on copywrite law or the legality of entering a fan game into a just-for-fun game jam. 
If you want more information or have more questions I will be writing and posting an FAQ in our discord.