I've searched the web for it, yet the only results were for something like an ordinary religion mod, which would allow you to create one, more or none based on your choices in its associated menus; however, what I'm looking for is a The Sims 2 mod that includes a mechanic similar to, if not the same as, the religions from The Sims Medieval. There are UI religion mods, or maybe they were hallucinated, but what I'm searching for is something that mimics the very religion mechanic from The Sims Medieval into The Sims 2.

Even if it is mostly aesthetic, it would be better than if it were entirely aesthetic. Basically, if it had almost no real affect on a Sim's life beyond, say, a daily sermon or an associated career track, that [all] would be better than something that has literally no other function than looking neat.

Also, it'd be neat if there were career tracks associated with said religions, namely Peterans and Jacobans, though Agnostics wouldn't logically have an associated career track (but that could be an option regardless) and possibly associated lot types or merely associated objects; I wonder if this sounds interesting or infuriating, preferring the former to the latter but not getting my hopes up, Yin-Yang &c.

I also hope that, if this already has existed, that at least one reply would direct me to it.

You might want to try posting this in the WCIF section.

In the meantime, you might find something by looking through Almighty Hat's Medieval resource list ...if you haven't already. The only religion mod that I am familiar with is the one by Chris Hatch, but it is not medieval specific.

Hat has a G-rated version here: https://hat-plays-sims.dreamwidth.org/55635.html

It has various settings, so you can probably modify it to your likings (including adding just two religions and name them whatever you want). Add in some medieval clothes and buildings, and you're right there alongside TSM. As for careers, there are plenty of custom and default replacement ones. It does have some affect on sims' lives, altering their behavior, but this is customizable (by you, ingame). Once set up, you can let it run its course through your sims' worlds.

I haven't tried it, but it does look to have some nice options if you're into it.

Sims is a game of pretend, so you can do whatever you like. There are things like working prayer books and sculptures, and clothes, buildings and objects that add to it.

It probably won't be exactly like TSM, but you can probably come close enough. It's been a while since I played TSM, but I seem to remember the religion thing wasn't particularly fleshed out.

Has anyone tried this religion mod? I'm so very curious...

I know it's a modified version of CH's mod, and plenty of people have used that. Hat's version is less than a month old, so it won't have gained as many users yet.