As the name suggests, the goal is to read all books across Hyrule.
These books are:
An Ancient Text (Fort Hateno) Camera Manual (Hateno Ancient Tech Lab) Castle Library Book (Hyrule Castle Library) Chef Aurie Taamu, Vol. 1 (Gerudo Town) Chef Aurie Taamu, Vol. 2 (Gerudo Town) Chief’s Diary (Gerudo Town) Girl’s Notebook (Hateno Village) Journal of Various Worries (Impa’s House, Kakariko Village) Kass’ Journal (Washa’s Bluff) King Rhoam’s Journal (King’s Study, Hyrule Castle) Misa’s Recipe Book (The Slippery Falcon, Rito Village) Mountain Peak Log (Mount Granajh) Paya’s Diary (Impa’s House, Kakariko Village) Purah’s Diary (Hateno Ancient Tech Lab) Robbie’s Memoirs (Akkala Ancient Tech Lab) Rumor Mill Vol. 1 (Enchanted, Kakariko Village) Rumor Mill Vol. 2 (Rito Village) Rumor Mill Vol. 3 (Outskirt Stable) Rumor Mill Vol. 4 (East Akkala Stable) Rumor Mill Vol. 5 (Wetland Stable) Rumor Mill Vol. 6 (Lakeside Stable) Rumor Mill Vol. 7 (Kara Kara Bazaar Inn) Selmie’s Notes (Hebra Trail Lodge) Sheikah Sensor Notes (Hateno Ancient Tech Lab) Sheikah Slate Manual (Hateno Ancient Tech Lab) The Old Man’s Diary (Old Man’s Cabin) Zelda’s Diary (Zelda’s Study) Zelda’s Research Notes (Zelda’s Study)
There are other books although these come with the DLC and the route I have written ( https://docs.google.com/document/d/1ZCDhBOmXYsTlxJAuqlZK70rtCZ1ZRMtR9fRyQrM43sY/edit?usp=sharing ) does not include these extra DLC books although there is nothing stoppping anyone from running ABEx (All Books + DLC)
Time starts upon gaining control of Link and ends when the text on the last page of the last book disapears.
With this scuffed route my guess is that a good run will take a bit over an hour.