If you look in the first post's "Repack Content" under 9.3, one of the links is to
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Every download I've been doing is from their Koitaku download, which as far as I'm aware is close to being fully up to date version RX3 (for whatever reason it's not showing up on that page directly, but going to their posts led me back to it here:
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)
If you look in the Mega folder link, it'll have a bunch of different versions available but the main one, as far as I'm aware, is the RX3 (last updated February 10th).
I should note that not 'every' mod is up to date (as other posters are pointing out, new version of kPlug might not be there yet, I haven't looked and it's in the Optional Mods folder even if it is, and when I downloaded it the pregnancy mod wasn't 1.2), and if you do want kPlug active then the last few pages have gone on in-depth to explain how to use it (it includes a manual if you look in the kPlug folder in Optional Mods after downloading).
Strictly in terms of "does it have DLC?", I think even the one here has it, but the DLC is kinda bare bones in terms of what it changes (it adds more date options and a janitor rape scene thing, but if you already downloaded a version and you see an option that says "The Darkness" in Free H mode then I think you have the DLC installed).
*oh yea should also note because you'll see it in the Mega folder: don't also download Koikatsu party. Koikatsu party, if I understand right, is 'just' the character creator tool and studio, and it's what is sold on Steam. Koikatsu, just by itself, is the 'full' version of the game sold in Japan, and has the actual adult content, if you look on the Steam page for Party, you'll see comments saying "go to the developer's site to download the free patch", which I'm assuming just makes it the full game with the lewds/story campaign. No comment on literally anything else in the folder, haven't looked up any of the other games.