Assuming a 15-10-5 arrangement of fleets, I presume the Americans and the Japanese will keep the following lineups of battleships.
USN
Nevada Class: Nevada, Oklahoma
Pennsylvania Class: Pennsylvania, Arizona
New Mexico Class: New Mexico, Mississippi, Idaho
Tennessee Class: Tennessee, California
Colorado Class: Colorado, Maryland, Washington, West Virginia
South Dakota Class: South Dakota, Montana
They'll also keep two theoretically-decommissioned battleships as training ships, probably the two New York Class: New York and Texas.
IJN
Kongou Class: Kongou, Haruna, Kirishima
Fusou Class: Fusou, Yamashiro
Ise Class: Ise, Hyuuga
Nagato Class: Nagato, Mutsu
Amagi Class: Amagi
They'll have one theoretically-decommissioned battleship as a training ship, which probably will be the last Kongou Class: Hiei.
Not too sure about Britain and Germany's lineups, due to the butterflies of Germany's Doolittle-esque victory at Jutland ITTL, along with the loss of the Queen Elizabeth to a U-Boat in the Mediterranean at the end of the war. At the very least, I presume Germany will only keep the Bayern Class Battleships from their wartime and pre-war fleet, and build modern battleships to fill their allotment of 10 battleships.