The Committee of Zero uploaded an uncensored overhaul patch for Chaos;Head Noah, and you can find it on its website. The page also leads to a spoiler-free guide if you wish to follow it and get every ending. This patch is available in both English and Japanese, and you can get it for Steam, Steam Deck, GOG, and Nintendo Switch.
The Chaos;Head Noah overhaul patch is not only uncensored, but it also fixes bugs and is an entirely original translation of the story. There are over 150 translated CGs, as well as additional subtitles and songs. The censorship mostly deals with content that Mages had to cut to lower the age rating for the PSP release. This patch will restore all eleven scenes (which are vital for a full experience) and the Lingerie Conversion Patch DLC.
There is a note from the translators explaining why they chose to re-translate Chaos;Head Noah. They strongly state that they support the translators who worked on the official release but they likely had little time or funds to get the translation to the level they wanted. There were so many mistranslations and inconsistencies, as well as out-of-character writing, that that the Committee of Zero had to re-translate it.
Chaos;Head originally came out in 2008, with the enhanced Chaos;Head Noah coming out in 2009. The story follows Takumi Nishijou, who experiences paranoia and hallucinations, which are a key gameplay mechanic. There has been a series of murders in Shibuya, called the “New Generation Madness” case, and Takumi finds himself wrapped up in it.
Chaos;Head Noah is available for the PC and Nintendo Switch, with the overhaul patch being available for all platforms.