Start the game with a saved file(that has been online) from Monster Hunter to unlock a fourth gallery page.
Blue Rathalos
Get a White Crown for Rathalos in trial mode.
Offline Lao
To unlock Lao offline, you must complete every offline quest including the hidden ones, unlock the three offline color variant wyverns and complete every trial quest. When you complete all of those conditions, Lao's quest will appear in the "Urgent" bracket of the offline quests.