I assume you have Spring 1942, so I’ll cover changes from that:
Carriers lost their attack point and can take 2 hits and cost 16. If they are damaged, they can’t land planes and any cargo planes are trapped. Battleships don’t automatically repair; you need a naval base to repair Battleships and carriers.
The 2 new units are mechanized infantry and tactical bombers
Mech:
Cost 4, Move 2, Attack 1, Defend 2
Mechs can move anywhere a tank can except that mechs can’t blitz unless paired with a tank. Artillery raise their attack to 2.
Tacs:
Cost 11, Move 4, Attack 3, Defend 3
Can land on carriers(which hold 2 ftrs, 2 tacs, or 1 ftr, 1 tac). If paired with fighter or tank, their attack increases to 4.